BMW Alpina B5 vs Mercedes-AMG E63

What's the difference?

The Alpina B5 is a special car – more special than most people will ever give you credit for if you own one. Those that do know what an Alpina is will let you know; people will cross dangerously busy streets to talk to you about your car. Insanely fast, almost incomprehensibly comfortable and effortlessly powerful to drive.

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.

Interesting is the right word for it, because while it might be questionable that Alpina's changes to the exterior are aesthetic pleasing, they are definitely intriguing to those who aren't familiar with the brand.

First, there are those 20-spoke wheels. Alpinas have worn this style of wheel forever and they've become the most famous outward sign that this is not just another BMW. So don't under any circumstances take them off and replace them with anything else. You'd be run out of town by the Alpina mafia.

Yes, they're more painful to clean than a cheese grater (trust me, I know. And if you look closely at these images you can see the dirty bits I've missed), but if you really don't like them then perhaps it's a sign this car isn't for you.

Then there's the boot-lid spoiler. It's square and 1980s'-looking, it also appears a bit like it's been bought online and installed by a teenager, but again, this is another Alpina tradition and it suits the car's character perfectly.

All right, those pinstripes; they're known as the Deco-Set and are a hat-tip to the Alpina racecars of the 1970s and '80s. Again, don't take these off, your Alpina will drop through the centre of the Earth in value. These are also part-and-parcel of owning one of these cars. I'm not a massive fan of them.

But I'm all about that front spoiler, with the floating Alpina lettering that you can option in silver, high-gloss black or gold.

Inside, there are fewer Alpina additions, but they're nonetheless unmissable. There's the Alpina-badged steering wheel, and a new virtual instrument cluster, embossed headrests and  illuminated door sills.

There's also the little numbered plaque on the centre console which proves its authenticity, ours was number 49. Out of how many? I don't know. But I do know Alpina produces only about 1700 cars globally a year. Rolls Royce does about 4000. So, you can rest assured your B5 is exclusive.

At almost 5m long, 1.9m wide and 1.5m tall, the B5 is a large saloon, but having recently reviewed the Alpina B7 it feels small in comparison. How does it drive? We're getting there.

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.

Practicality is not really a BMW strong point no matter which model you pick. See, BMW mostly makes the car equivalent of uber-stylish and skin-tight active wear which looks good and performs brilliantly, but sometimes you just want pockets and a bit of room for your… um… bits and pieces.

So while there are two cup holders up front and two in the back, the bottle holders in the doors aren't huge, the centre console bin is on the small side, there's a hidy-hole in front of the shifter, the glove box is just a box for little more than gloves and there's no other great cabin storage options.

Legroom in the rear is good but not great, too - I'm 191cm tall and have about 30mm between my knees and the seat back in my driving position. Middle-seat passengers will also have to straddle the drive shaft hump in the floor. Headroom is restricted in the back, too (you could blame the sunroof) with my hair just skimming the headlining (I do have big hair).

Under that power tailgate, the B5's boot capacity is 530 litres which is 15L more than its big sister, the B7. There are two plastic storage areas either side of the luggage space for wet things. While there is one USB outlet in the front there aren't any in the rear.

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.

The Alpina B5 uses the same 4.4-litre V8 engine found in the BMW M5 (and also the B7). But, and it's a big but, the M5 makes 441kW and 750Nm, while the B5 outdoes it with 447kW and 800Nm. Admittedly, the B5's torque arrives at the 3000rpm mark, while the M5's is all there from 1800rpm.

How does the B5 beat it? Alpina installed its specially developed twin turbochargers and intercoolers, a high-performance cooling system, a reconfigured air intake set up and a different exhaust system.

The B5, though, is a tenth of a second slower to 100km/h compared to the M5 with a time of 3.5 seconds, but it will blast on to a top speed of 330km/h while the M5 is limited to 250km/h in regular form and 305km/h with the optional M Driver's package.

Both uses the same ZF eight-speed automatic transmission with identical gear ratios, and both are all-wheel drive.

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.

The Alpina B5 needs petrol. By that, I mean it needs quite a lot of it if you want to enjoy it properly. What type of mileage does it get? Officially, it should use 11.1L/100km after a combination of urban and open roads, where as the M5 is set to 10.5L/100km.

That makes sense, the B5 produces more power and torque, and it's 85kg heavier than the M5 at 2015kg.

Our test car's trip computer was reporting 13.2L/100km after flying low over country roads and slow city piloting. The more time spent in the urban warfare that is the daily peak hour commute, the more that figure crept and hovered around the 15L/100km mark.

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.

Ok, stay with me here. For this next bit you'll need a fresh egg, a lounge chair, and it might be a good idea to have some plastic bags and carpet cleaner on hand.

First, in front of the lounge chair flatten out the plastic bag and place the egg on it. Next, sit down on the chair and very carefully rest the ball of your foot on the egg with as little pressure as humanly possible.

This is exactly how little force you need to apply to the go-pedal of the B5 to accelerate from a standstill to 60km/h in about five seconds.

If anything sums up the driving experience of the B5, it's that sense of effortlessness.

Stomp on that accelerator, and you'll be shot to 100km/h in 3.5 seconds, without a hint of broken traction thanks to the all-wheel-drive system.

The ride should have been terrible on 20-inch wheels shod in low-profile rubber (Pirelli P Zero 255/35 front, and 295/30 rear), but the Alpina-tuned air suspension is close to miraculous in the way it cushioned and censored the potholes out of Sydney's worst roads. Yes, it can be a touch floaty, particularly in the Comfort Plus setting, but this is benchmark-setting stuff for a comfortable ride.

Don't expect this beast to roar. Unlike the M5, the B5 gets its work done without deafening everybody around it. Sure, the B5's V8 sounds amazing when you push it, but it's not brash, not loud and not lairy. Buy an M5 or Mercedes-AMG E63s if you want to be heard half a block before you get home, but you won't get that with the B5 and its exhaust system.

The B5 also handles well, but I have to say the engagement factor is low. I piloted it effortlessly through the twists and turns of my country test circuit and roads which normally have me grinning like a maniac behind the wheel had me feeling a bit disconnected in the B5. That air suspension, the numb steering and pedal actions make it difficult to ‘feel' the road.

It's highways where the B5 is a king, but even at 110km/h there's the sense that this car is still fast asleep and won't get out of bed for anything less than 150km/h - making it perfect for Germany's autobahns, but maybe not for here in Australia.

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.

The Alpina B5 is covered by BMW's three-year/unlimited kilometre warranty. Servicing is recommended every 12 months or 15,000km.

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.