BMW XM vs Mercedes-Benz Gls600

What's the difference?

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 big, it’s bold and totally baller, but that’s kind of the point.

The Mercedes-Maybach GLS 600 might not win over many fans with its in-your-face design or its sky-high price tag, but there is definitely an appeal here.

Taking luxury to another level is no easy feat, especially in a Mercedes, but the attention to detail, lavish second row and butter-smooth V8 engine combine to turn the already-good GLS into this exquisite Maybach.

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

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.

If you have wealth, why not flaunt it? I reckon that might be the philosophy of the Maybach designers back at HQ, and it kind of shows!

The styling of the Maybach GLS might be the most controversial thing about it. But honestly, I love it!

The liberal lashings of chrome, the three-pointed star hood ornament, and especially with the optional two-tone paintwork, it’s all just so over the top and in your face that it brings out a smile.

From the front, the Maybach is also distinguished by an imposing grille that gives it serious presence on the road, while the profile is characterised by massive 23-inch multi-spoke wheels – better park well clear of any gutters!

You’ll also notice the Maybach eschews the usual black-plastic cladding around the wheelarches and underbody found on lesser/cheaper SUVs in favour of body-coloured and gloss-black panels.

There is also a little Maybach badge on the D-pillar, which is a nice attention-to-detail touch. From the rear, there’s more chrome, while the dual exhaust outlets hint at the performance on offer. But it’s inside where you really want to be.

Everything in there is just a sea of soft-touch and premium materials, from the dashboard to the seats and even the carpet under your feet.

Though the layout of the interior mirrors the GLS, the extra detailing, like the Maybach-stamped pedals, unique multimedia surround and woodgrain steering wheel, elevates the cabin into something truly special.

And if you opt for the comfort rear seats, well they wouldn’t look out of place on a private jet.

The second-row seats also feature contrast stitching on the headrests, cushions, console and doors for that add a touch of class.

I can see the Maybach GLS might not be to everyone’s tastes, but it certainly stands out from the sea of samey-looking luxury SUVs out there.

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 Maybach GLS is based on Mercedes’ largest SUV offering to date, which means there is plentiful room for occupants and cargo.

The front row feels positively palatial, with heaps of head-, leg- and shoulder-room for six-foot (183cm) tall adults.

Storage options include generous door pockets with room for large bottles, two cupholders, a smartphone tray that doubles as a wireless charger, and an underarm storage cubby.

But the rear seats are where you want to be, especially with these second-row comfort seats fitted.

It’s rare when there is more room in the rear than the front, but it does makes sense for a car like this, especially when you consider the GLS this car is based on is a three-row vehicle.

The removal of seats six and seven mean there is more room in the second row, especially with the comfort seats fitted, allowing you to recline fairly flat and to get into a comfortable position.

Storage is also plentiful in the second row, with a bespoke centre console in our test car, the aforementioned drinks fridge, backseat storage and a nice door bin.

Open the boot and you will find 520 litres (VDA) of volume, which is plenty for golf clubs and holiday luggage.

However, if you opt for the rear seat refrigerator, the cooler box will eat into boot space.

The best things in life might come free, but the most luxurious things certainly come at a cost.

Wearing a price tag of $378,297, before on-road costs, the Mercedes-Maybach GLS 600 is probably out of the reach for most mere mortals, but there’s no denying Mercedes has thrown in a lot for the spend.

And with it positioned nearly $100,000 north of the Mercedes-AMG GLS 63 ($281,800) – with which it shares its platform, engine and transmission – you’d want to get a bit of bang for your buck.

Standard features include keyless entry, push-button start, Nappa leather interior trim, a head-up display, a sliding glass sunroof, power-closing doors, heated and cooled front and rear seats, and interior ambient lighting.

But, as the epitome of Mercedes’ luxury SUVs, the Maybach also scores 23-inch wheels, a heated woodgrain and leather steering wheel, open-pore wood trim and five-zone climate control – one for each passenger!

Handling multimedia duties is Mercedes’ 'MBUX' 12.3-inch touchscreen display, complete with satellite navigation, Apple CarPlay/Android Auto support, digital radio, a premium sound system and wireless smartphone charger. 

Rear seat passengers are also treated to an entertainment system with TV tuner so you can keep up with the Kardashians from the road, as well as a bespoke MBUX tablet with functions for climate, multimedia, satellite navigation input, seat controls, and more.

Sadly, the Samsung-branded tablet glitched out a few times while we were using different functions and required a reset.

No doubt, a software update can fix some connection issues, but it's still something that shouldn’t be happening in a high-dollar, ultra-lux SUV.

Options with the Maybach GLS are surprisingly limited, with buyers able to choose between different exterior colours and interior trims, second-row comfort seats (as fitted on our test car), and a rear champagne chiller box.

Look, nearly $400,000 for an SUV might seem like a lot, but you really are wanting for nothing with the Maybach GLS, and it's comparable in price to other high-end SUVs like the Bentley Bentayga and Range Rover SV Autobiography.

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.

Powering the Mercedes-Maybach is a 4.0-litre twin-turbo petrol V8 – the same engine you will find in many AMG products like the C 63 S and GT coupe.

In this application, the engine is tuned to produce 410kW and 730Nm, which is admittedly less than you get in something like the GLS 63, but the Maybach isn’t designed to be an outright powerhouse.

With drive sent to all four wheels via a nine-speed automatic transmission, the Maybach SUV will accelerate from 0-100km/h in just 4.9 seconds – also helped by a 48-volt mild-hybrid 'EQ Boost' system.

Though not designed for outright grunt, the Maybach GLS’s engine is nicely tuned to deliver smooth power and seemless shifting

The Maybach is more than a match for rivals such as the Aston Martin DBX (405kW/700Nm), Bentley Bentayga (404kW/800Nm) and Range Rover P565 SV Autobiography (416kW/700Nm).

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.

Official fuel consumption figures for the Mercedes-Maybach GLS 600 are pegged at 12.5 litres per 100km, and it’s recommended to fill up with 98 RON premium unleaded, so be prepared for a big fuel bill.

This is despite the 48-volt mild-hybrid tech that lets the Maybach coast without using fuel in certain conditions, and extends start-stop functionality.

In our brief time in the car, we managed to get 14.8L/100km. Why is the Maybach so thirsty? That’s simple, it’s weight.

All the cool features like Nappa leather interior, woodgrain trim and 23-inch wheels add weight to the overall package, and the Maybach GLS tips the scales at nearly three tonnes. Ouch.

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.

While you might not find many owners of the Maybach GLS in the driver’s seat, it’s nice to know it can hold its own in the driving dynamics department.

Don’t get me wrong, this won’t give the AMG-blessed GLS 63 a run for its money, but the Maybach SUV is far from dull.

And the engine plays a large part in this. Sure, it’s not as savage as some AMG models, but there is still plenty of grunt to come out of corners with enthusiasm.

The tune of the engine is obviously weighted towards smoothness and comfort, but with 410kW/730Nm on tap there is enough there to make things feel urgent.

The nine-speed automatic transmission also has to be called out, as it is calibrated in such a way that the shifts are imperceptible. There’s none of that mechanical jerkiness and clunkiness involved in swapping cogs, and it just makes the Maybach GLS feel that much more luxurious.

The steering, while straying a towards numb, still offers plenty of feedback so you know what’s happening underneath, but it’s the active body control that works to keep this hefty SUV in check in the bends.

The best bit, though, has to be the air suspension, which floats the Maybach GLS over bumps and uneven roads like a cloud.

The front-facing camera can also read the terrain ahead and set-up the suspension for incoming speed bumps and turns, taking comfort up to a whole new level.

All this is to say, yeah, the Maybach might look like a boat, and cost as much as a boat, but it doesn’t actually feel like a boat behind the wheel.

But really, are you buying this car because you want to be the driver? Or are you buying one because you want to be driven?

In the second row, it’s as close as you’ll get to a first-class flight on the road, and the seats are genuinely plush and cosy.

It’s eerily quiet and supremely comfortable in the second row, leaving you free to carry on with important business like drinking your champagne or uploading to the 'gram.

And while I usually suffer from a bout of motion sickness within minutes of looking at a phone in a car, I didn’t feel such ill effects in the Maybach GLS.

Even after about 20 minutes scrolling through Facebook and emails while being driven around, there was no sign of a headache or queasiness, which is all thanks to how well the suspension is tuned and the active anti-roll technology doing its thing.

The Mercedes-Maybach GLS 600 has not been tested by ANCAP or Euro NCAP, and therefore doesn’t wear a safety assessment rating.

Despite this, the safety equipment found on the Maybach is comprehensive. As standard, there are nine airbags, a surround-view camera system, autonomous emergency braking (AEB), tyre pressure monitoring, traffic sign recognition, front and rear parking sensors, rear cross-traffic alert, and automatic high beams.

Mercedes’ 'Driving Assistance Package Plus' is also included, bundling adaptive cruise control, lane-keep assist and blind-spot monitoring.

The 'Urban Guard' suite also adds an alarm, tow-away protection, parking damage detection, and an interior motion sensor, which can send notifications to your 'Mercedes Me' app.

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.

Like all new Mercedes models sold in 2021, the Maybach GLS 600 comes with a five-year/unlimited kilometre warranty with roadside assist over that period.

This is class-leading in the premium segment, with only Lexus, Genesis and Jaguar able to match the warranty period, while BMW and Audi serve up assurance periods lasting only three years.

Scheduled servicing intervals are every 12 months or 20,000km, whichever occurs first.

While the first three services will cost owners $4000 ($800 for the first, $1200 for the second and $2000 for the third service), buyers can opt to save some money with a pre-paid service plan.

Under the service plan pricing, three years of maintenance will cost $3050, while four- and five-year plans are on offer at $4000 and $4550 respectively.