Mercedes-Benz Eqs450 vs Audi S8

What's the difference?

Does electrification enhance the seven-seat SUV experience? In the case of the EQS450, the answer is yes. Smoother, quieter and with plenty of easy-flowing power, the brand's family-focused luxury electric SUV behaves exactly as you might expect.

Note: CarsGuide attended this event as a guest of the manufacturer, with meals provided.

The S8's existence is a source of joy for me because it's not a huge SUV. Yes, it's a huge sedan but it's a reminder that the technological flagship is alive and well, at least in Germany. And the important thing about these cars is the way the toys filter down through the rest of the range. That used to take years but we're seeing this cool stuff a lot more quickly, right down to the A1.

The S8 punches, and punches hard in this rarefied part of an already shrunken section of the market - the twin-turbo V8 matches its German rivals, it's lighter and it's as well-stacked as any of the three. What it doesn't do, however, is shout about itself the way the other two do.  It's the incognito choice.

It’s a handsome SUV, and one that’s not immediately recognisable as electric — especially given there are little exhaust-pipe-mirroring design flourishes at the rear which make you look twice.

Aussie-spec cars get the AMG exterior treatment, which includes AMG alloys, aluminium-look side steps and the power-domed bonnet, but there's still nothing overly 'shouty' about the design, with the sleek, smooth body panels (accentuated by the hidden handles) making the EQS450 look smaller than it actually is.

Inside, it’s a super-comfy space to spend time, and the little fluffy pillows attached to the headrests should be standard in every car. The tech on offer is ample, too.

But it does all feel a little gigantic, with great swathes of wood panelling and massive screens, all of which make you feel bit like you’ve been shrunken down and are now living amongst the giants.

The sheetmetal is obviously very restrained given it's an Audi first, and secondly, it's just not done to go wild in this part of the market.

It's an A6 that's joined a gym, but didn't join that weird gym with men that can't run after you when you insult them (don't ask how I know this). Rolling on 21-inch wheels as standard, you can go up to massive 22s if you so choose.

The A8 created a subtle redirection of Audi's passenger car look, with the updated A4 and A6 both picking up on the horizontal bar between the rear lights and the huge grille framed by family lights with signature DRL patterns. The S8 builds on that with subtle S cues but nothing even vaguely shouty.

The interior acreage - or 'cabin', if you will - is very comfortable, but you already knew that. The multi-screen layout was first seen in the A8 and has now found its way into A7, Q8 and Q7 and is, as ever, brilliant to look at and use.

The MMI updates that have found their way into other cars are present and correct. Like the exterior, it's very restrained but not to the point of sparse minimalism, despite the lack of switches and buttons.

I really don't like the steering wheel, though, and I can't put my finger on why. It certainly isn't especially sporty-looking but I wonder if the standard flat-bottomed S wheel just looked stupid.

The materials are beautiful and everything fits together perfectly.

The EQS450 stretches 5136mm in length, 1965mm in width and 1718mm in height. That's about the size of a Nissan Patrol and long enough to make it a proper seven-seater.

The middle row can be adjusted forwards or backwards, and with the front seat set to my 175cm driving position, I found I had ample head and knee room to get comfortable.

USB-A charge points abound, and there's wireless device charging, and because of the sheer size of the cabin, the storage options are plentiful. The central bin between the front seats, for example, seems styled on the Grand Canyon.

In the third row, though, things get a little tighter, but it’s perfectly good for kids. My knees were touching the seat in front, however, and it still requires some acrobatics to climb into.

At the rear, with all three seats in place, you'll find 245L of room (measured to the ceiling), growing to a maximum 1030L with the third row flat. Stow the second row, and you'll find a maximum 2020L of storage space – which, and take my word for it – is plenty.

One small quirk, though. While the second row is electric, stowing away at the touch of a button, the third row isn't. That means, when it's flat, you have to climb into the boot to pull it back up, or attack it from the rear door. Either way, it's more awkward than it needs to be.

The cabin is clearly built with rear seat passengers in mind, with rear leg and headroom configured for those continent-crossing drives.

The S8 has plenty of comfort for two rear seat passengers and a few amusing options to while away the hours in traffic or on the autobahn.

That doesn't mean the front seat passengers are in purgatory, with huge but supportive seats adjustable in all conceivable directions.

Front and rear rows score a pair of cupholders and bottle holders while the boot is a handy, if not awe-inspiring, 505 litres.

For $260,000 there is a lot to get through, as there is on the less sporty A8. Start with huge 21-inch alloys, 17-speaker Bang & Olufsen stereo, panoramic sunroof, matrix LED headlights with laser lights, soft-close doors, acoustic glazing, leather trim, S front seats, extra leather over the A8, Alcantara headlining, carbon inlays, four-zone climate control, heated and cooled front seats, 'Virtual Cockpit' with S mode, and a tyre repair kit.

You also get active suspension, a sport version of the 'quattro' all-wheel drive system (with a sport differential), and a walloping great twin-turbo V8 to get you moving.

A massive touchscreen on the centre stack (familiar in Q8, A7 and Q7) hosts Audi's 'MMI plus' system, which is very good and does away with the console-mounted rotary controller. It also has wireless Apple CarPlay to go with the console-bin wireless charging pad. Android Auto is still USB. 'Audi Connect plus', now in full-featured glory, is also along for the ride.

Another technical highlight is the active noise cancelling which is meant to reduce the noise in the cabin the same way noise cancelling headphones do.

There's a clever rear seat remote control, which is a little detachable tablet to allow those who are being chauffered to faff around with various settings.

Our car had the $13,900 'Sensory Package', which adds a 1820-watt B&O 3D sound system with 23 speakers, electrically adjustable outer rear seats along with heating, cooling and massage function, and full leather.

There are two electric motors delivering the driving power, one at the front axle and one at the rear, which will deliver a combined 265kW and 800Nm, fed through a single-speed transmission and with all four wheels being powered.

That's enough for a sprint to 100km/h of 6.0 seconds.

Under that long bonnet is a 4.0-litre twin-turbo V8 pumping out 420kW and a diesel-like 800Nm of torque. 

That's a lot, even for this big bruiser. Obviously, being an Audi S-car, it has quattro all-wheel drive, which is fed by an eight-speed ZF automatic. Which is in everything now. Well, just about.

That huge torque figure is available between 2000rpm and 4500rpm while peak power arrives at 6000rpm. The 0-100km/h sprint is despatched in - gulp - 3.8 seconds.

As it's riding on the MLB platform, the mild hybrid system is a 48-volt set-up. A lithium-ion battery in the boot takes charge from the belt alternator/starter, which means the S8 can coast at higher speeds with the engine off and also cut out at 22km/h and under in traffic.

The system can also add up to 60Nm of torque in the right conditions for up to six seconds, and if it happened for me, I didn't notice it.

There's a huge 107.8kWh on board here, but the EQS450's driving range is a less impressive 483km. Maybe something to do with the 2918kg weight of this big SUV.

Don't get me wrong, 483km is plenty to cover almost anyone's weekly commute (and then some), but early promises had pointed to a range of more like 600km.

When it comes time to plug in, you'll find the EQS450 is set up for 200kW DC fast charging, which should see you go from 10 to 80 percent charged in just 31 minutes.

Home charging is, of course, a slower proposition. A three-phase 11kW supply should take 10 hours, while a 7.0kW wallbox will be slower again, and more like 15 hours.

The 10.5L/100km official figure is, shall we say, optimistic. The launch drive was mostly highway so there's no real information to be gleaned from that, so we'll have to wait for real world fuel figures.

I'd say 12-13L/100km is achievable if you don't like having fun, in which case, the lesser A8 is probably for you.

Audi says the MHEV system saves 0.8L/100km with an early cut-out for the stop-start and the ability to coast on the highway for over half a minute at a time.

The drive experience is, well, unremarkable. But I don’t want that to sound negative, because that's not how it's intended.

The EQS450 SUV does exactly what you expect a circa-three-tonne, premium electric SUV to do, and it does it all well.

It's powerful enough without being exhilarating, comfortable enough, and laden with enough tech to satisfy almost anyone.

It's just that it also doesn't exactly ignite the senses. But the question must be asked, what seven-seat family-focused SUV does? Few, if any.

So, surely the real test is if electrification has improved the formula here, and I'd argue that it definitely has.

For one, the EQS450 is properly whisper-quiet in the cabin, with Benz employing multiple sound-deadening techniques at once to lock out road noise. And with no pesky engine to interfere, the cabin is about as serene as they come.

The power delivery is predictably smooth and easy, too. There is no headline-stealing acceleration figure here, but the power is potent and plentiful, and more than enough for any real-world situation you might encounter.

The ride, too, is commendable. Aided by Mercedes' air suspension, it glides over all but the most broken road surfaces. And it is fitted with rear-axle steering, which really does cut down a turning circle that would otherwise surely resemble that of a cruise ship.

It feels heavy at times, though, and even the most high-tech suspension can't eliminate body roll entirely through tighter corners (physics and all that).

But unless you're really pushing – and why would you be – the cabin is calm, comfortable and cosseting.

So, exciting? Not really. But comfortable and calming, which are probably the traits its owners will value much higher.

Driving any of the cars in this segment is a rare treat, whether it's the 'entry level' diesel or this top of the heap sports sedan. My day with the S8 was filled with the usual surprise and delight that only these tech-packed cars can deliver.

Heading out of the Sydney CBD in 'Comfort' mode, the car scans the road ahead and adjusts the active suspension accordingly. You already know it has active suspension because when you pull the door handle, the car lifts by 50mm to make it a bit easier to get in.

The suspension's party trick is flat-topped speed bumps - drive at one, brake a little and sense the way the body feels like it stays exactly where it is in the air but the suspension almost completely flattens the speed hump.

It's uncanny and almost unnatural, with just the tiniest change in altitude and no noise from the suspension.

It also manages the terrible narrow lanes of CBD thoroughfares with ease, the lane keep system letting you know if you're straying.

On to the motorway and you get a feel for its crushing performance. You won't hear much, though - the stereo's noise-cancelling system shuts out almost all tyre noise and consistent wind noise is largely banished, too.

I'm going to admit I gasped when I found some corners. Active suspension bodes well for the tricky stuff, as does the all-wheel steering. Both are exceptionally clever systems for making the car feel a lot smaller in town and in car parks but they're also really good if you want some fun.

But the way the rear-wheel steer adds agility to such a big car is hilarious and clever. While you can't quite chuck it around - and really, you're not buying an A8-sized car for that kind of nonsense - brisk progress is far from intimidating.

Now, obviously, a Ford Fiesta would drive away from the S8 in the really tight stuff but it would take some time to properly shake it. The colossal torque from the V8 hurls even this two-tonne-plus limo out of the corners in a most satisfactory manner.

It's surprisingly agile for a machine more than five metres long and two metres wide. If your passengers are corner enthusiasts, you'll all be having fun in near silence. It's oddly engaging to be moving at pace in such a hushed cabin.

The S8's considerable safety equipment list includes nine airbags, ABS, stability and traction controls, forward AEB (up to 250km/h), reverse cross-traffic alert, lane departure warning, various collision mitigation and protection systems, exit warning, lane keep assist, active cruise control and on, and on, and on.

The rear seat's centre airbag is terribly clever, popping up between passengers to stop you knocking heads. Another clever trick is the way the car detects a side impact is about to happen, boosting the height of the side about to cop it to try and get the sills to take more of the impact, rather than the door.

Given the relatively niche status of the A8, let alone the S8, there is no ANCAP crash test or safety rating. One imagines given the ton of safety gear a five star rating is all but assured. Even the US IIHS gave the A8 a miss.

The Mercedes EQS450 is covered by Mercedes-Benz's five-year, unlimited-kilometre warranty, with servicing required every 12 months or 25,000km.

You can prepay your service costs, coming in at $2350 for three years, $3695 for four years or $4280 for five years.

The battery its covered for eight years or 160,000km.

Audi continues to fail to match Mercedes move to a five year warranty, sticking with three year/unlimited kilometre cover. BMW is still doing it too, so maybe Ingolstadt and Munich are playing chicken. 

You can get a five-year service plan for the S8, coming out at $3990 for the duration.