Audi A8 vs Mercedes-AMG E63

What's the difference?

The Audi A8 swims in a luxury car shark tank where those paying the big dollars expect top-shelf everything. It delivers a serene driving experience whether you’re in the front or the back, in a superbly engineered and executed luxury sedan package. Not perfect, but very, very impressive.

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.

The A8 is close to 5.2 metres long, yet instantly recognisable as an Audi thanks mainly to its evenly weighted proportions, gently curved roofline and overall high-waisted design. Worth noting its drag coefficient (Cd) is an impressively slippery 0.25.

The characteristic look is accentuated by the brand’s signature, six-sided grille, in this instance highlighted by a matrix of high-relief chrome accents. And typically angular LED Matrix headlights sit either side.

Check out our video review for the carefully orchestrated animation they run through when the car is unlocked.

The car looks equally svelte and contemporary from the rear, with just the right amount of chrome lifting the tone and multi-spoke 20-inch rims filling the wheel arches nicely.

As you’d expect, the top-shelf look and feel continues inside with the seats trimmed in aniline leather, perforated on the front and outer rear positions, with genuine hide also covering the centre console, door rails and armrests, steering wheel and upper dashboard.

Fine grain ash wood inserts sit alongside brushed metal elements and a meticulous attention to detail is obvious… everywhere.

For example, the interior door handle design has been thoroughly thought through, requiring a simple underhand tap to open the door, rather than the more conventional, and ergonomically convoluted, ‘over the top’ movement.

Three sleek screens dial up the tech - a 10.1-inch multimedia interface at the top of the centre stack, an 8.6-inch display below it for heating and ventilation, and a 12.3-inch version of Audi’s ‘Virtual Cockpit’ in the instrument binnacle.

And the spacious rear is the epitome of cool, calm Teutonic form and function. You feel relaxed the moment you get in, and isn’t that the primary aim of a car like this?

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.

Space is luxury, be it a large house, a first class seat or a spacious car, and at nearly 5.2 metres long with a close to 3.0m wheelbase the Audi A8 measures up. 

Even before you get in, the doors have an amazing sense of solidity and quality. It’s like opening and closing a bank vault… if that huge circular door had a power-assisted soft-close function. 

There’s copious amounts of space for the driver and front passenger with lots of storage including a lidded box between the front seats, complete with a two-piece longitudinally split top design, so you can sneak your half’s open without displacing your neighbour’s elbow.

The door bins are decent but there isn’t a specific cut-out for bottles, so it’s more a case of laying them down than standing them up. There’s also a handy covered cubby at the end of the door armrests.   

The glove box is a good size and there are two cupholders under a pop-up cover in the centre console.

Of course, the back is where space really counts, and there’s as much room as you’d find in, well… a limo.

Sitting behind the driver’s seat, set for my 183cm position, I enjoyed copious amounts of head, shoulder and legroom. 

There are electric sunblinds for the rear and rear side windows, controlled by buttons in the door as well as the rear seat remote, a 5.7 inch OLED display housed in the beautifully trimmed fold-down centre armrest (which also has a soft close function!). The remote also allows adjustment of the lighting and climate control. Classy.

There’s a shallow storage box and twin cupholders in the armrest, medium size door bins and hard shell pockets on the front seat backs. The rear armrests also feature a small lidded cubby. 

In terms of connectivity and power options there’s wireless Android Auto and Apple CarPlay, a USB-A and USB-C in the front, and an identical pair in the rear, as well as a 12-volt socket in the front and two in the back.

Boot volume is a useful 505 litres (VDA) and the lid is electric, with gesture control. It’s able to easily swallow our three-piece luggage set or the bulky CarsGuide pram. And while the rear seats don’t fold there’s a ski port door to accommodate long items. Just make sure you use the tie-down anchors in the boot to ensure they’re properly secured. There’s a handy netted section behind the left wheel well and a cargo net is included.

Maximum towing capacity, for a braked trailer, is 2.3 tonnes (750kg unbraked) and in more good news, the spare is a space-saver rather than the increasingly prevalent inflator/repair kit.

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 Audi A8 50TDI is powered by a 3.0-litre turbo-diesel V6 engine sending 210kW (from 3500-4000rpm) and 600Nm (from 1750-3250rpm) to all four wheels via an eight-speed automatic transmission (with ‘Tiptronic’ sequential manual shift function) and Audi’s quattro constant all-wheel drive system using a self-locking centre differential.

It also features a 48-volt electrical set-up for mild hybrid functionality built around a belt connected starter/generator, AC to DC converter and a 48-volt lithium-ion battery. 

With energy recovery of up to 12kW from regenerative braking, it enables the A8 to regularly coast with the engine switched off and helps the extended stop-start system to operate smoothly. 

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.

Audi’s official fuel economy number for the combined (ADR 81/02 - urban, extra-urban) cycle is 6.6L/100km, the 3.0-litre turbo-diesel V6 emitting 175g/km of CO2 in the process.

Over a week of city, suburban, and some freeway running we averaged 11.1L/100km, which is acceptable for a 2.1-tonne luxury sedan.

Also worth noting the standard stop-start system works beautifully thanks to the 48-volt starter/generator.

You’ll need 82 litres of diesel to fill the tank and using the official number, that translates to a range of just over 1240km, which drops to around 740km using our real-world figure.

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.

Despite extensive use of aluminium in the ‘ASF’ platform and body panels, the A8 tips the scales at a sturdy 2095kg, yet Audi says the A8 will accelerate from 0-100km/h in just 5.9 seconds. And with 600Nm of peak torque available across a flat plateau from 1750-3250rpm this big four-door gets up and goes hard when asked to. 

At more sedate speeds you’re occasionally reminded there’s a diesel engine under the bonnet, with that characteristic engine and exhaust noise only making their presence felt under pressure. 

In fact, under normal circumstances, noise, be it the engine, tyres or wind is minimal, thanks to a combination of the car’s aero-efficient shape, thick acoustic glass and other sound-deadening measures throughout the car.

The eight-speed auto transmission is suitably smooth, with the central shifter or wheel-mounted paddles able to make snappy sequential ‘manual’ shifts.

There are four drive modes in the ‘Drive Select’ system - ‘Comfort’, ‘Auto’, ‘Dynamic’ and ‘Individual’ - enabling tweaks to the steering, transmission, throttle and suspension. Comfort felt most appropriate most of the time, although dialling up the throttle and transmission to more aggressive modes in Individual adds an enjoyable edge.

The suspension is five-link front and rear with an adaptive air system smoothing even high-frequency bumps and ruts amazingly well.

Push into a corner and the A8 feels nicely balanced, its wide track, sophisticated suspension, plus the quattro AWD system seamlessly distributing drive between the front and rear axles, keeping the big body under control. In fact, you feel the ‘big car shrinking around you’ syndrome from the get-go.

The steering is precise without being overly sharp and road feel is good. Again, with that 2.1-tonne kerb weight in mind, braking is appropriately powerful with big ventilated discs front (350mm) and rear (330mm).

It pays to remember the turning circle is 12.5m, and it’s worth picking your spot for a U- or three-point turn.

Although there’s a lot going on for the driver in terms of screens, buttons and switches it all makes sense ergonomically. The head-up display is helpful and there’s a common sense mix of digital and physical controls, the latter including an audio volume knob. Yes.

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 A8 is covered by Audi Australia’s five-year/unlimited km warranty, which is now par for the luxury market course, and 24-hour roadside assistance is included for the duration.

Paint defects are also covered for five years, with rust (to the point of perforation) covered for 12. Nice.

Service is required every 12 months or 15,000km with a five-year capped-price plan for the A8 coming in at $3830, or $766 per year. That’s a fair wedge but not outrageous for the category.

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.