Mercedes-Benz Eqs450 vs BMW XM

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.

It’s pretty obvious the XM is designed to impress people with big wallets and an appetite for a techy experience that’s also not without a few green credentials. The ability to motor around as a fully-electric vehicle for up to 80km or so is a big plus and the electric-ballroom interior vibe is hard to ignore, as well.

But from our perspective, the full-fat, twin-turbo V8, while offering startling performance, is perhaps a lost opportunity to follow some of BMW’s competitors into the engine-downsizing space. Then again, when you floor the throttle and 2700kg hurtles forward like a big dog on a short chain, you can see where BMW is coming from.

Perhaps the biggest letdown is the ride quality – or lack of it. While it’s understandable BMW wanted the most dynamic version of the XM it could manage, the end result plays against the vehicle’s otherwise long suit of hyper-luxury. Doubtless, BMW would argue that to soften the chassis would have been to introduce a chink into a no-compromise product. But, perhaps, sometimes a sensible compromise is the way forward.

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.

There’s nothing subtle about the way the XM looks. It probably pulls up just short of brutalist (or maybe not) but even those who find its slabs and angles attractive have to admit that it’s bold.

The now-trademark giant nostrils set the mood and the rest of the exterior suggests some kind of armoured transport for presidents rather than wheels for the school run. Doubtless, this will hardly be seen as a fault by those in the market for such a thing.

The real surprise here is that the XM does not share a bodyshell with any other production BMW. Sure, the V8 petrol engine and wheelbase are common to other BMW and M models, but the sheet metal is the XM’s and the XM’s alone. That in itself, is quite a statement of intent.

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.

Given the vast exterior dimensions and a weighbridge ticket the wrong side of 2700kg, it may come as a surprise to learn that the XM is strictly a five-seater with not even an optional third row.

That said, the uber-SUV Lexus LX in flagship, Ultra Luxury, trim offers just four seats in deference to the VIP clientele it’s pitched at, but also comes complete with reclining rear seats and a passenger’s side footrest which the XM can’t match.

Staying in the rear seat, there’s lots of legroom and plenty of space under the front chairs for feet. A lot of that is down to the wheelbase the XM shares with the BMW X7, and even behind a tall driver, there’s lots of space. In fact, compared with a BMW X5, there’s a full 150mm of extra legroom.

The pew itself flows into the door trims for a lounge effect which looks great with the contrasting light-coloured trim, and the centre arm-rest folds down to reveal a pair of cupholders. Extra storage space can be found in fold-out pockets in the rear of each front seat which also house a small, lidded panel that opens to reveal USB ports and power sockets. Dual-zone climate controls are also part of the rear-seat experience.

The gee-whizz stuff hasn’t been ignored, either, and the prismatic roof lining is nothing if not a talking point. But would a panoramic sunroof have been of more value to many buyers? The ambient lighting is a nice touch, too.

Up front, the view is dominated by the giant, twin curved animated dashboards. They deliver information and lots of it, to the point where it can almost seem a bit overwhelming.

The head-up display helps simplify things, but there’s absolutely no doubt there’s a lot going on in this cabin. Again, this is modern luxury motoring, but it remains that the menu system will take time to learn, even if the touchscreen function gives you an option on how you control things.

Multi-adjustable front seats are part of the deal and there’s an M-spec steering wheel which is heated. And although it features plenty of buttons, isn’t as daunting perhaps as the multi-spoked equivalent in some high-end AMGs of late.

The stereo system is also worthy of a mention, being a Bowers & Wilkins unit with roof mounted speakers and no less than 1500 watts of power. Digital radio is part of the package.

Even though it doesn’t offer a seven-seat option, luggage space in the rear of the XM is hardly class-leading. Cargo volume with rear seat up is 527L and 1820L with it folded.

Much of the wheelbase is devoted to rear-seat stretching room and although the batteries for the electric motor are positioned under the rear seat, the floor of the cargo area seems quite high.

The XM is one of those 'no options' vehicles. That is, you pay the basic price, you get one with the lot. The aged leather and even the optional 23-inch wheels and tyres are no-cost options, so it’s clear where BMW is aiming the thing.

As well as the plug-in driveline, all-wheel drive and all the M driving focus, the XM features plenty of tech including massaging front seats, heated seats all around, a high-end stereo, heated and cooled cupholders, four-zone climate-control, wireless phone charging and twin, curved info screens for the driver measuring 12.3 and 14.9 inches. The novel roof lining also features 100 pin-point LEDs for effect.

The cost of such detailing is a not insubstantial $302,200. That figure does, however, undercut two of its main rivals, the Lamborghini Urus ($395,888) and the Aston Martin DBX ($356,512).

It’s also worth mentioning that the XM is not even BMW Australia’s most expensive model; in fact, it’s fourth on the ladder.

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.

Here’s where the XM starts to justify its price-tag. While the use of an electric motor to boost a petrol engine has allowed some manufacturers to reduce the capacity of the latter, no such restraint has been shown for the XM. Instead, it gets the full 4.4-litre, twice turbocharged V8 that we’ve come to know and love from this brand.

It’s not that this is the engine’s first date with hybrid technology, but the mild hybrids that have come before it can’t match the XM for sheer brutality when both power units are unleashed.

The petrol V8 can muster up 360kW and 650Nm which, when boosted by the electric motor, jumps to a total of 480kW (combined) and 800Nm.

While the petrol engine drives through an eight-speed torque-converter automatic, the electric motor also drives through the transmission, an arrangement that is a bit different to some hybrids which use the petrol engine for the rear axle and the electric motor to drive the front wheels.

Of course, the requirement for the XM to feature permanent all-wheel drive, regardless of what power unit is running at the time, forces this layout.

Speaking of all-wheel drive, The XM’s version of BMW’s 'xDrive' layout has been specifically tuned for this vehicle and includes torque vectoring as well as a limited-slip rear differential.

The system has the ability to vary the torque split front to rear, with the default rear-bias giving a more sporting feel on good surfaces. An active rear differential also helps give the car a rear-drive feel.

As well as modes for 'Hybrid', 'Electric' and 'eControl' modes, the XM sticks with the M tradition of offering two M buttons which can be configured to set the parameters for steering, driveline, chassis and, in the case of the hybrid XM, the degree of braking regeneration offered.

Four-wheel steering is also part of the XM’s repertoire and, interestingly, there’s no air suspension here; just conventional steel springs.

But it does feature an electrically-adjusted anti-roll bar system which aims to strike a happy medium between what the driver wants and the road conditions demand.

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.

A 25.7kWh lithium-ion battery provides the power for the electric drive. It’s mounted under the rear seat and can produce a purely electric range of between 82 and 88km (based on WLPT test protocols).

Charge time from a conventional wall-box is said to be about four hours but, interestingly, the XM has no provision for DC fast-charging.

Fuel consumption (combined cycle) is an EV-typical 2.7 litres per 100km, which equates to a low 61g/km of CO2.

Once you’ve depleted the battery on a highway journey, expect the petrol V8 to consumer somewhere between eight and nine litres per 100km at cruising speed.

Using EV mode means zero-emission operation but, as with any electric car, how the power is generated to recharge it determines its real-world green-ness.

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.

While any M car is supposed to be rapid and dynamic, it’s also true that the over-arching perception of big SUVs is that they’re comfortable and plush. None of which explains the ride in the XM.

Regardless of how you fiddle with the settings, the ride is always brittle. Those big tyres with their minimal sidewall somehow manage to find every crack and join in the road, and it’s these sharp-edged imperfections that thump through to the cabin the most vocally.

It’s enough to make you wonder who this car is going to appeal to. Will it take to race tracks? Almost certainly not. So the whole point of these suspension settings might be a bit lost on some people.

Performance, meanwhile, is insanely rapid for something that could pass as a bulk carrier. The biggest giveaway to the mass is the transmission’s earnest attempts to keep everything moving by feeling a bit hyperactive on downshifts.

Using the ratios is always going to be the strategy, but with all that torque, maybe it’d be nice sometimes for the trans to hang on to a taller gear and let the boost blow it towards the next corner.

The sound track? Polarising. Even if it doesn’t convince you that Hans Zimmer (who developed the various electronically-synthesised noises the XM makes) should stick to winning Oscars, the augmented sounds are background noise rather than the main event here.

Even the petrol V8’s naturally stirring backing vocals have been electronically tweaked with debatable results.

That said, it’s nice to have something to listen to that isn’t the insistent tyre roar which becomes even louder on coarse-chip surfaces.

Steering effort is light but there’s not a lot of feedback in terms of actual feel. In fact, it’s borderline detached and only the sheer speed of the rack confers any athleticism.

Also, the rear steering seems to come in a few milli-seconds after the front has started to turn. And for all that all-wheel-steering agility, this is never a car that shrinks around you.

As well as the usual passive safety features, the XM also hides the latest active safety gear. In fact, BMW reckons the XM has more driver assistance than any other M car before it.

Those elements start with the 'Driver Assistant Professional' which bundles active cruise-control with stop-go ability, steering and lane-keeping control, automatic speed limit assist and active navigation.

Parking assistance is also featured which incorporates a reversing assistance function, front, rear and panoramic camera views with a 3D view built in.

BMW’s 'ConnectedDrive' includes an emergency call function in the event of a crash or other emergency.

No ANCAP assessment so far.

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.

Like a lot of manufacturers, BMW knows consumers can be leery of EV tech when it comes to the cost of battery replacement. So, as well as the five-year/unlimited-kilometre warranty on the whole vehicle, there’s also eight years or 160,000km of cover for the high-voltage battery.

Servicing intervals are based on how the car has been used and it will inform the owner when a service is required.

A servicing package is included in the purchase price and BMW even throws in three years of roadside assistance.