BMW 840I vs Mercedes-AMG E63

What's the difference?

If you’re the sort of buyer who wants a car that signifies a lifestyle that is ‘large and in charge’, the BMW M850i Gran Coupe could be just the thing for you. It isn’t as showy as some of its competitors, and mightn’t reach the same levels of excitement as those cars either - but it is a convincing offering in its own right, and a beautiful piece of design at that. 

The E 63 S fills its niche in AMG's Australian line-up perfectly. More mature than the brand's four-cylinder hatches and SUVs, but not as overbearing as some of its bigger sedan, GT and SUV stablemates. And its ability to seamlessly switch between serene comfort and dynamic performance has nailed the objective for this 2021 update.

This could be BMW’s most convincing design in years. I mean, the X5 is predictably handsome, the X3 was unexpectedly muscled, and the less said about the frumpy 1 Series and busy 3 Series (apart from the wagon… drool) the better.

To my untrained but enthusiastic eye, the 8 Series Coupe is a bit too rounded over its rear haunches, and the rear screen is just a little steep - to me, that lets its dimensions down a little. But this. This is gorgeous. 

I mean, you might have questions over the tail-light design, which is a theme across a few BMW models now. But there isn’t as much confrontation between horizontal and vertical graphics for this model as you’ll find one other big Bimmers, like the X7. 

The M850i model has BMW Laserlight headlights, which throw a sharp beam and look menacing in their signature, while the grille and bumper are strong. The stance of the car is prominent - there’s a long body, a long wheelbase, and a long body in general. The standard wheel package consists of 20-inch rims, and they don’t look disarmingly large.

As our images show, there’s a lot to talk about when it comes interior design and finishes, but the cabin doesn’t quite benefit quite as mochas you might think it would from all that real estate. I mean, with dimensions of 5074mm long (on a 3023mm wheelbase), 1932mm wide and 1402mm tall, this is a squat, yet substantial vehicle. It’s just more cramped than you’d think inside.

The E 63 S has been massaged for 2021 starting with flatter headlights, AMG's now signature 'Panamericana' grille, and a high gloss black flap across the top of the curved 'Jet Wing' section defining the lower part of the nose.

At the same time, the vents on either end of it are larger and feature twin transverse louvers to guide cooling air to wherever it's needed.

It's all about what AMG calls 'optimised aerobalance' but the form is just as appealing as the function. The characteristic 'Power Domes' in the bonnet dial up the muscle, as do the fat wheel arches (+27mm each side), and 20-inch rims with distinctive aero inserts.

This car's optional exterior carbon package consists of a front splitter, side sills, a flash near the fender badges, the exterior mirror covers, the boot lid lip spoiler, as well as the lower apron around the redesigned diffuser and quad tailpipes.

New, intricately styled LED tail-lights are also flatter, but there's even more going on inside.

A new AMG sports steering wheel features three rounded twin-spokes with new switches on the bottom to control the car's dynamic set-up.

It also picks up a new take on the small touch-sensitive controllers used to adjust the instrumentation and manage other functions like phone calls, audio and the cruise control.

Not sure I'm in love with them at this stage. In fact, the words fiddly, imprecise, and frustrating come to mind.

Nappa leather covering the superb AMG sports seats, upper dash, and door beltlines remains standard, but the show-stopper is the 'Widescreen Cockpit' - twin 12.25-inch digital screens for the MBUX multimedia interface on the left and instruments on the right.

The instrument cluster can be set to 'Modern Classic', 'Sport' and 'Supersport' displays, with specific AMG read-outs such as engine data, gear speed indicator, warm-up status, car set-up, as well as a G-meter and 'RaceTimer.'

To borrow an official automotive design term, it looks schmick. Overall, with touches like open-pore black ash wood trim, and brushed metal highlights, the interior looks efficient but classy, with an obvious attention to detail in the layout and its execution.

I recall a Mitsubishi designer telling me, once upon a time, that he dreamed of making ‘a big car on the outside with a very small interior’. Maybe he made the jump to BMW, because that’s pretty much the 8 Series Gran Coupe.

There aren’t many other vehicles on the market, of this size, that offer less space inside. The boot capacity, for instance, is just 440 litres. Competitors like the Audi A7 (535L) and Mercedes CLS (520L) easily outdo it - but at least this car has more boot than the Panamera (405L), though the BMW is a smidge bigger. The cargo space is large enough for a couple of overnight suitcases, but you’re hardly going to fit a family of four’s luggage for a week away. 

And while we’re in the “not quite what you’d expect” column, the back seat space is hardly commodious. There’s enough space for me, at 182cm, to sit behind my own driving position, but not without wishing for a bit more toeroom, headroom and knee space. 

The big centre console section eats into the space in the rear, justifying the brand’s “4+1” seating claim, and unpleasantly it has a hard plastic finish to rest your leg against. Getting in and out of the second row isn’t easy for bigger people, and it’s quite a squat down into the rear seat - it really has taken inspiration from its squashy-back-seated predecessor in that regard.

If you have smaller rear-seat occupants, however, there will be catered for with dual ISOFIX and three top-tether points, plus there are air vents with climate controls (quad zone in total), and two USB-C ports as well. There are sun-blinds on the rear windows, too, which is a plus, and there is a pair of cup holders in the fold-down armrest, and map pockets in the seat backs, too. The door pockets are near-useless, though.

The front seats score better practicality, with bottle holders in the doors, bigger and sturdier cup holders, a covered centre storage bin between the seats with a USB-C port, and a wireless phone charger (Qi) with standard USB port in front of the gear selector.

Above that is the weird, very out-of-place quick buttons (1-8) that BMW could easily do away with, and further up are the controls for the climate control (thankfully with hard buttons for fan speed and temperature), and above that is the media screen, a familiar looking 10.25-inch touch display running BMW OS 7.0. 

The screen is quick and crisp, and is backed up by the rotary controller and buttons on in the centre console area. There’s wireless Apple CarPlay (now at no cost for three years), as well as a built-in SIM card for 4G data and access to the BMW Online news and weather stations, accessed through the screen.  

It’s all pretty easy to use, and the sound system is excellent - the standard setup consists of 16 speakers, with DAB+ digital radio, Bluetooth and USB plus the smartphone mirroring tech, provided you don’t have an Android device, as Android Auto is still missing from BMW’s range.

It’s a nice cabin, but I couldn’t help but thinking that I’d want a little more differentiation from the lesser models in the range if I was spending this much. Especially considering the optional cost of the interior trim fitted to our test car - see below for more detail.

At just under 5.0m end-to-end the E-Class sits in the upper range of the mid-size luxury spectrum. And almost 3.0m of that is accounted for by the distance between the axles, so there's plenty of space inside.

The driver and front passenger are provided with heaps of room to breathe, and there's a surprising amount of space for those in the back as well.

Sitting behind the driver's seat set for my 183cm (6'0”) position I had more than adequate head and legroom. But access to and from the back is a struggle for full-size adults.

The rear doors open out a long way, but the limiting factor is the size of the aperture, necessitating excessive contortion of the head and limbs to fold in and out of the car.

Connectivity runs to two (power-only) USB-C sockets in the front centre storage bin, as well as another USB-C (for power and multimedia) and 12-volt power outlet in the centre console.

Speaking of the front centre storage bin, it's a decent size and has a padded split lid so it can double as an armrest. There are two cupholders in the front console, a generous glove box, as well as long door compartments with recesses for large bottles provided.

There's a pair of USB-Cs along with another 12-volt socket in the back, sitting under the climate control panel with adjustable vents in the rear of the front centre console. Nice.

The fold down centre armrest incorporates a lidded (and lined) storage box as well as two pop-out cupholders. Again, there are bins in the doors with room for smaller bottles.

The boot offers 540 litres (VDA) of volume, and is able to swallow our three-piece hard suitcase set (124L, 95L, 36L) with room to spare, or the substantial CarsGuide pram, or the largest suitcase and pram combined! There are tie-down hooks to help secure loads, too.

Don't bother looking for a spare of any description, a repair/inflator kit is your only option. And the E 63 S is a no-tow zone.

So, first of all, let's get the price out of the way. At $253,900, before on-road costs, this car's competitive set is a bruising, all-German trio comprising the Audi RS 7 Sportback ($224,000), BMW M5 Competition ($244,900), and Porsche Panamera GTS ($309,500).

And no surprise, it's loaded with all the luxury features you'd expect in this part of the market. Here are the highlights.

On top of the standard performance tech and safety equipment fitted to the E 63 S (covered later in this review), you'll also find: Nappa leather trim (seats, upper dash, upper door cards, and steering wheel), MBUX multimedia (with touchscreen, touchpad, and 'Hey Mercedes' voice control), 20-inch alloys, three-zone climate-control, interior ambient lighting, auto LED headlights (with 'Active High Beam Assist Plus'), eight “energising comfort programs” (with 'Energising Coach'), an 'Active Multicontour' front seat package, the 'Air Balance' package (including ionisation), and keyless entry and start.

Also included are the the 'Widescreen' digital cockpit (twin 12.25-inch digital screens), 13-speaker Burmester audio with digital radio, Apple CarPlay and Android Auto, a panoramic sunroof, adaptive cruise control, a head-up display, augmented reality satellite navigation, 'Parktronic' self-parking, electric front seats, seat cooling and heating front (heated rear), heated front centre armrest, a power-adjustable steering column, auto rain-sensing wipers, a wireless device charger, illuminated door sills, as well Amazon Alexa, etc, etc, etc.

And our test car also featured a couple of tasty options. An exterior carbon package ($7500), and AMG's professional grade ceramic composite brakes ($15,900), for an as-tested price of $277,300.

If you’re going for the M850i, you’re getting the big bopper engine. It’s a 4.4-litre twin-turbo V8 petrol engine, and it isn’t short on horsepower.

The outputs for this engine are 390kW of power (at 6000rpm) and 750Nm of torque (from 1800-4600rpm). Hardly numbers to sneeze at.

And the performance figures are exceptional, too: the claimed 0-100 km/h time is just 3.9 seconds. That’s because there’s the traction of BMW’s xDrive all-wheel drive system, and shifting gears is an eight-speed automatic transmission.  

For what it’s worth, your humble reviewer saw a 0-100km/h time very close to that (4.2sec). 

The quoted kerb weight for this model is 1995kg.

The E 63 S is powered by the M178 version of the all-alloy 4.0-litre twin-turbo V8 engine used across numerous AMG models from the C-Class up.

Thanks in no small part to direct injection and a pair of twin-scroll turbos (located in the engine's 'hot vee' to optimise throttle response), this all-alloy unit produces 450kW (that's 612hp) from 5750-6500rpm, and 850Nm from 2500-4500rpm.

And as per standard AMG practice for its Vee engines, this car's powerplant was built from scratch by a single engineer in Affalterbach. Thank you Robin Jäger.

AMG calls the nine-speed transmission used in the E 63 S an MCT, which stands for Multi-Clutch Technology. But it's not a dual-clutch, rather a normal auto transmission using a wet clutch as opposed to a conventional torque converter, to connect it to the engine on take-off.

Drive goes to all four wheels via Merc's '4Matic+' AWD system, built around an electromechanically controlled clutch connecting the permanently driven rear axle (with locking diff) variably to the front axle.

You can’t really expect a big V8 beast like this to be a fuel miser, and it isn’t.

The claimed consumption is 10.7 litres per 100 kilometres. Which is alright, honestly, given the sheer volume of car you’re driving. 

But on my test - which consisted of more than 300km of mixed driving, including days of city commuting, some twisty mountain driving, and all the freeway floundering to get there - I saw an at the pump real-world figure of 15.4L/100km.

That’s not very efficient, and it’ll be expensive to run on the daily — yet the argument could be made that if you’re spending this much on a car, fuel costs won’t matter much to you. But with a small fuel tank capacity of 68 litres, it could become a little inconvenient as you’ll be seeing a lot of your local servo.

Claimed fuel economy for the combined (ADR 81/02 - urban, extra-urban) cycle is 12.3L/100km, the E 63 S emitting 280g/km of CO2 in the process.

That's a pretty hefty number, but in line with this car's proportions and performance potential.

And Merc-AMG has gone to great lengths to minimise fuel use. As well as the standard 'Eco' stop-start function, in the 'Comfort' drive program cylinder deactivation becomes active, the system able to drop four cylinders anywhere between 1000 to 3250rpm.

There's no physical hint of half the cylinders leaving the party. The only clue is a blue icon on the dash indicating a temporary shift to V4 operation.

Despite all that effort, however, we saw a dash-indicated 17.9L/100km over a mix of urban trundling, highway cruising, and some spirited dynamic assessment.

Recommended fuel is 98 RON premium unleaded (although it'll run on 95 at a pinch), and you'll need 80 litres of it to fill the tank. That capacity translates to a range of 650km according to the factory claim, and 447km using our real world result.

It’s an impressive thing, this M850i xDrive Gran Coupe. But I’m just not sure who it’s trying to please.

It’s not the sort of German monster coupe-sedan that grabs you by the scruff of the neck and throws you around with its mammoth acceleration. Not unless you poke it and prod it and make it really angry.

And that might be exactly what you want to do - put it in Sport mode, sling the shifter across to sport or manual mode, hear the exhaust open up from a pursed-lip tongue-click to an open-mouth growl. 

You’ll push hard on the accelerator, watch the tacho needle jolt to the redline, and if you’re in auto mode you’ll feel the transmission whipcrack as it shifts rapidly up through the gears as you’re shoved back into your seat. Before you know it you’ll be in licence-loss zone, and you won’t have even made the tyres chirp - that’s how immense the traction from the all-wheel drive system is.

You’ll brake hard into a sharp bend, and you’ll feel the front end dip and the body of the car change direction more readily than you’d think given its size as you turn in. The steering response will meet your expectation, with rapid reaction to adjustments mid corner. And the Active Roll stabilisation system will mean you’re not being thrown around in your seat, because it’s sitting flatter and truer than you might have expected - you’ll notice how it works extremely well in conjunction with the car’s torque-vectoring-by-braking system. There’ll be little weight shift or body roll to be counteracted, and that’ll inspire you to push it even harder.

Put it in manual transmission mode and you’ll rejoice that it won’t overrule you and shift up, but you’ll also feel shortchanged because it gets to the end of its limit very quickly. And when it hits redline, it emits a breathless little cough rather than a “oh maybe I should stop” rev-bounce noise.

But, if you’re like me, you might be doing all this with a niggling thought in the back of your mind that, while this car is technically really good and it’s a clinical performance car, you might just think to yourself, “I’m not having as much fun as I thought I would”.

A Mercedes-AMG would be more fun; it’d be more raucous, more of a muscle car experience. An Audi RS7 (at least the previous one) would be noisier, brasher, more theatrical than this car. And likewise, a Porsche Panamera - no matter the model you go for - would be more entertaining in the bends.  

Maybe it’s just a bit too predictable - and maybe that’s a result of this car being honed for drivers who will spend more time on the Autobahn than anywhere else. I have to say, there are much, much worse (and slower) ways of getting from A to B, and the highway cruising comfort of the M850i Gran Coupe was what impressed me most. 

It’s also surprisingly adept at urban driving duties, coping well with unpleasant city surfaces, though potholes can still upset things because of the stiff-sidewalled run-flat tyres. The suspension does an exceptional job otherwise, however, and I switched between the Adaptive drive mode and Comfort mode for my commuting duties. Both proved comfortable and controlled.

The M850i is by no means a failure when it comes to fulfilling the expectations you might have of a luxury sports sedan of this size. In fact, it’s close to a distinction. But I just can’t help thinking that it’s not as much an ‘M car’ as that M850i badge might have you believe it should be.

AMG's major goal with this upgrade of the E 63 S was to maintain its dynamic response and ferocious performance, but dial in the extra comfort customers had said they wanted.

So, the 4Matic+ AWD system has been fine-tuned for more smoothness as has the Comfort option in the dynamic set-up. But we'll investigate that shortly.

First, that 4.0-litre turbo V8 in the nose is claimed to slingshot this roughly 2.0-tonne sedan from 0-100km/h in just 3.4 seconds, and it feels every bit that fast.

With 850Nm available from 2500-4500rpm and nine gear ratios to help keep you operating in that Goldilocks band, mid-range thrust is monumental. And thanks to the bi-modal sports exhaust it sounds beautifully brutal.

The nine-speed auto's wet clutch, as opposed to a conventional torque converter, is designed to save weight and optimise response. And while some will tell you an auto with one input shaft is never going to be as fast as a dual-clutch with two, shifts are rapid and direct. The wheel-mounted shift paddles are larger and set lower, as well.

The AMG 'Ride Control+' suspension with multi-chamber air suspension and adaptive damping is amazingly good. The underlying set-up is by multi-links front and rear, and despite riding on big 20-inch rims wrapped with low-profile, high-performance Pirelli P Zero rubber (265/35 fr - 295/30 rr) the Comfort setting is incredibly... comfortable.

Slip into 'Sport' or 'Sport+' and the car immediately feels tauter but far less compliant and forgiving. An impression reinforced by the engine, transmission, and steering shifting to a more buttoned-down mode at the same time.

The standard dynamic engine mounts play a big part here. Able to make a soft connection for maximum comfort, but switch to a rigid link when required.

But no matter which mode you're in, the car is well damped and feels beautifully balanced in quick cornering. And the E 63 S's electro-mechanically-assisted variable-rate steering is progressive, feelsome, and accurate.

The 4Matic+ AWD system is built around an electromechanically controlled clutch connecting the permanently driven rear axle (with locking diff) variably to the front axle.

Torque distribution happens imperceptibly, the big V8 putting its power down emphatically, with various electronic systems tieing up the loose ends as you aim up for the next corner.

 There's even a 100 per cent RWD Drift mode available in the Race setting, but without a race circuit at our disposal this time around that'll have to wait for another time.

The optional ceramic brakes feature huge rotors and six-piston front calipers, and stopping power is immense. And the good news is they operate quickly but progressively at normal pottering around town speeds. No warming up required to get them in an optimal temperature zone (as can be the case with other ceramic set-ups).

The three-pointed star's white-coated boffins have gone to town on the E 63 S, and the car is as good as it currently gets in terms of active and passive safety technology.

You could argue this car's dynamic ability is its strongest contributor to crash-avoidance. But a broad suite of features, specifically designed to keep you out of trouble includes, forward and reverse AEB (with pedestrian, cyclist, and cross-traffic detection), traffic sign recognition, 'Attention Assist', 'Active Blind Spot Assist', 'Active Distance Assist', 'Active High Beam Assist Plus', 'Active Lane Change Assist', 'Active Lane Keeping Assist', and 'Evasive Steering Assist.' That's a lot of assists.

There's also a tyre pressure monitoring and pressure loss warning system, as well as a brake priming function (monitors release speed on the accelerator pedal, moving pads factionally closer to the discs when required), and brake drying (when the windscreen wipers are active the system periodically applies just enough brake pressure to wipe water off the brake rotors to optimise wet weather efficiency).

But if an impact is unavoidable the 'Pre-Safe Plus' system is able to recognise an imminent rear-end collision and fire up the rear hazard lights (at high frequency) to warn following traffic. It will also firmly apply the brakes once the vehicle is stationary to minimise the risk of whiplash injuries if the car's then hit from behind.

If the potential crash is coming from the side, 'Pre-Safe Impulse' inflates air chambers in the side bolsters of the front seat backrest (within a fraction of a second) moving the occupant to the side towards the centre of the car, away from the impact area. Amazing.

As well as that, there's an active bonnet to minimise pedestrian injuries, an auto emergency call function, 'Crash Response Emergency Lighting', even a first aid kit and hi-vis vests for all occupants.

For the record, the current E-Class received a maximum five-star ANCAP assessment in 2016.

BMW backs its cars in Australia with a three-year/unlimited kilometre warranty.

You may be confused if you head to the BMW site and see that M models and 8 Series models aren’t covered by BMW’s pre-pay capped price servicing plan (as I saw when testing this car), but CarsGuide can confirm that the 8 Series is indeed covered - unless it’s the real M8, not this M850i jigger. 

BMW Australia has clarified that the Service Inclusive pack for five years/80,000km of maintenance cover is $2490 for Basic cover (no brakes/pads, no wiper replacement), or $5641 for the more comprehensive Plus pack. Hardly affordable, but nor’s the car. 

The company uses a condition-based servicing program, too - there are no set service intervals, but the car will tell you when it needs maintenance based on how you drive it.

For what it’s worth, we ran the numbers on resale value using Glass’s Guide predictive analysis tool, and after three years/40,000km the expected retained value for this version is approximately 66 per cent - which is impressive.

All AMG models sold in Australia are covered by Mercedes-Benz's five year/unlimited km warranty, with 24-hour roadside and accident assistance included for the duration.

Recommended service interval is 12 months or 20,000km, with pricing for a three-year (pre-paid) plan set at $4300, a $950 saving overall relative to its three year, pay-as-you-go 'Service Solutions' capped price program.

And if you're happy to fork over a little more up-front, there's a four-year service deal at $6300, and five years coming in at $7050.