BMW M Models vs Mercedes-Benz GLS

What's the difference?

Brutal, bruising and utterly brilliant, the M4 CS will be an acquired taste due to its no-compromise approach, but those willing to take the leap will find a performance car like few others at their disposal.

The GLS63 is an intimidating beast from afar, but it rewards its occupants in almost every way. Yep, there really isn’t a box it doesn’t tick without serious compromise, such is its breadth of capability.

If there was ever a Swiss Army Knife of cars, the GLS63 is definitely a contender for the title, one that makes it very hard to wipe the smile off your face. Just make sure you can fit it in your garage first…

The M4 CS is familiar in all the right ways, but definitely looks significantly jacked up compared to its lesser siblings.

Part of that is the extensive use of carbon everywhere, from its bonnet panels to its roof, front lip, side skirting and boot spoiler. But also because of its super-muscular angles and creases, including the huge dome in its bonnet.

Also exclusive to this M4 CS is the light treatment, with the front LEDs lighting up with yellow highlights the brand says are supposed to be reminiscent of GT racing cars.

At the back, the rear lights are flush with fibre optic lighting, lending a flowing and unique light signature that looks epic at night.

Inside, it's a sea of carbon, with the lightweight racing seats, the dash inserts and the centre console all lined in it. It is a perfectly finished space, though, and one that's also flecked with red, including a 12 o'clock band on the thick-rimmed steering wheel, the seat backs, the contrast stitching and the paddle shifts.

Be warned, though, it takes some acrobatics to climb into or out of the CS. The seat bottoms have these super high edges that double as grab handles, but require some awkward contortions to navigate.

In short, it looks angry, this M4 CS, inside and out.

If the GLS63 was a Marvel superhero, it would undoubtedly be the Hulk. Simply put, it has road presence like few others. In fact, it’s frankly menacing.

Of course, the GLS is already pretty intimidating due to its sheer size and blocky design, but the GLS63’s full-fat AMG treatment takes it to another level.

Naturally, the GLS63 gets an aggressive body kit, with its purposeful bumpers, side skirts and rear spoiler serving as instant reminders of what you’re dealing with, but it’s AMG’s signature Panamericana grille insert that really hammers home the point.

Around the side, the GLS63’s 22-inch alloy wheels with staggered tyres (front: 275/50, rear: 315/45) make their presence known, positioned below the wheelarch extensions.

That said, some fun’s also had at the rear end, where the GLS63’s diffuser element integrates the foreboding sports exhaust system with quad tailpipes very neatly.

The focused Multibeam LED headlights also look the part, while the opposing LED tail-lights tie everything together outside quite nicely.

Inside, the GLS63 stands out from the GLS crowd with its sports steering wheel with Dinamica microfibre accents, and multi-contour front seats, which are covered in Nappa leather alongside the armrests, dashboard and door shoulders and inserts.

Of note, the doors bins are unfortunately of the hard plastic variety, which is very disappointing in a vehicle that costs this much. You would expect that cow hide would also been applied to them, but alas it isn’t.

The GLS63’s black headliner serves as an obligatory reminder of its sporting intent, and while it makes for a dark cabin, metallic accents are prominent throughout, while the optional trim (our test vehicle had carbon-fibre) mixes things up, alongside the ambient lighting.

And let’s not forget the GLS63 is still loaded with plenty of cutting-edge technology, including a pair of 12.3-inch displays, with one the central touchscreen and the other the digital instrument cluster.

Both are powered by Mercedes’ class-leading MBUX multimedia system and feature Apple CarPlay and Android Auto support. This set-up arguably remains the best there is today thanks to its speed and breadth of functionality and input methods.

It all boils down to how you classify practicality in a car like this. I mean, the basic stuff is all there – it's got two doors, four seats and a boot capacity of 440 litres.

It measures 4801mm in length, 1918mm in width and 1399mm in height, and room for front seat riders is good, but less so for anyone you squeeze into the back. There are even ISOFIX points for a child seat.

But if you consider practicality the practical pursuit of performance, then the M4 CS has plenty of perks.

Measuring 5243mm, 2030mm wide and 1782mm tall with a 3135mm wheelbase, the GLS63 is an upper-large SUV in every sense of the term, which means it’s also very practical.

For example, cargo capacity below the load cover is decent, at 355L, but stow the 50/50 power-split-folding third row via the boot and it’s very good, at 890L, or drop the 40/20/40 power-split-folding middle bench, too, and it becomes a cavernous 2400L.

Better yet, the boot’s aperture is almost square, and its floor’s flat, while there’s no load lip to contend with, making loading bulkier items even easier. Up to four tie-down points are also on hand (depending on seating configuration) to secure loose cargo.

Under the false floor is the space-saver spare, which is to be expected, but what isn’t expected necessarily is the fact there’s also enough room there for the cargo cover when it’s not in use, which would be the case if six or more passengers are regularly onboard.

Moving into the power-sliding second row, the GLS63’s practicality is once again brought to the fore, with up to six-plus inches of legroom available behind my 184cm driving position.

There’s also two inches of headroom with the panoramic sunroof in situ, not to mention just enough toe-room. The GLS63’s small transmission tunnel and sheer width also mean three adults can be seated on the middle bench with few complaints.

Amenities-wise, the second row has map pockets on the front-seat backrest and a small fold-down cubby below the rear climate controls, with it containing two slots for smartphones and a pair of strategically placed USB-C ports.

The rear door bins can take one large bottle each, while a fold-down central armrest is also on hand, featuring a shallow tray and retractable (and flimsy) cupholders.

Alternatively, the $2800 Rear Seat Comfort Package fitted to our test vehicle subs in a tablet that can control the multimedia system, a wireless smartphone charger and a small cubby into the former, as well as a heated/cooled cupholder atop the rear of the centre console.

In the third row, it’s not quite as roomy if you’re an adult. With the middle bench in its most accommodating position, my knees still brush up against its backrest, which is to be expected given it’s primarily designed for children. I also have an inch of headroom there.

Nonetheless, getting in and out of the third row is relatively easy as the power-operated middle bench tumbles forward and provides just enough space to make entry and exit somewhat graceful.

When seated, rear occupants are treated to two USB-C ports and one small cupholder each, so they’re arguably taken better care of than those in the middle.

Child seats are well and truly accommodated, with four ISOFIX and five top-tether anchorage points fitted across the second and third rows, although the latter will inevitably prove to be a much tighter fit.

The driver and front passenger are still taken care of, with a front cubby taken up by two heated/cooled cupholders, a wireless smartphone charger, two USB-C ports and a 12V power outlet, while their door bins take one large and one small bottle each.

In-cabin storage options include the large central storage bin, which hides another USB-C port, while the glovebox is on the smaller side, with about a third of it taken up by the fragrance, which is pumped into the cabin to ensure the interior always smells its best.

Priced from $255,700 plus on-road costs, the GLS63 commands a $34,329 premium over its predecessor, although buyers are arguably getting more bang for their buck than before, even if it does sit well clear of the two other GLS variants: the $147,100 GLS450 and $153,900 GLS400d.

Standard equipment not already mentioned in the GLS63 includes regular metallic paintwork (our test vehicle was finished in Selenite Grey), dusk-sensing lights, rain-sensing wipers, power-folding side mirrors with heating, soft-close doors, roof rails, rear privacy glass and a power-operated tailgate.

Inside, keyless entry and start, augmented reality (AR) satellite navigation with live traffic, digital radio, a 590W Burmester surround-sound system with 13 speakers, a head-up display, a panoramic sunroof, heated seats (including middle outboard) and armrests, cooled front seats with massaging functionality, power-adjustable seats, a power-adjustable steering column, temperature-controlled front cupholders, five-zone climate control, stainless-steel pedals and an auto-dimming rearview mirror feature.

With BMW not offering an X7 M (although the slightly smaller $209,900 X5 M Competition is available) and the $208,500 Audi RS Q8 really from the segment below, the GLS63 does not have a direct rival in the Upper-large SUV segment.

In fact, the $334,700 Bentley Bentayga V8 is actually the model that comes closest to the GLS63 when looking for a seven-seater with a similar level of bent-eight performance.

BMW has found yet more grunt lurking in its trusty 3.0-litre 'M TwinPower' six-cylinder petrol engine, with the M4 CS now pumping out 405kW and 650Nm.

That's a decent jump from the 390kW and 620Nm served up by the M4 Competition, and a giant leap from the outputs of the 'base' M4 – 353kW and 550Nm.

Predictably, then, the CS is the fastest of the lot, knocking off the run from 0-100km/h in 3.4 seconds, compared to 3.5 and 4.2 in the Competition and M4, respectively. The top speed is also dialled up to 302km/h.

All that power is channeled through an eight-speed automatic and sent to all four wheels on demand, with the help of an 'Active M Differential'.

The GLS63 is powered by a familiar 4.0-litre twin-turbo V8 petrol engine, with its version producing a thumping 450kW of power at 5750rpm and 850Nm of torque from 2250-5000rpm.

This unit is mated to a nine-speed torque-converter automatic transmission and AMG’s fully variable 4Matic+ all-wheel-drive system with torque vectoring and a rear limited-slip differential.

This set-up also features Mercedes’ EQ Boost 48V mild-hybrid system, which actually gives a 16kW/250Nm electric boost in short bursts, such as when accelerating off the line.

Speaking of which, the GLS63 sprints from a standstill to 100km/h in just 4.2 seconds, while its top speed is electronically limited to 250km/h.
 

The M4 CS is fitted with a 59-litre fuel tank, which – given the BMW's official fuel claim of 10.2 litres per hundred kilometres – should deliver a driving range on a full tank of 541 kilometres.

But... BMW also says the regular M4 – you know, the one that makes 52 fewer kilowatts and 55Nm less torque – uses 10.1L/100km, so do with that information what you will.

The GLS63’s fuel consumption on the combined-cycle test (ADR 81/02) is 13.0L per 100km, while its carbon dioxide emissions are 296 grams per km. All things considered, both claims are unsurprisingly high.

In our real-world testing, we averaged a fearsome 18.5L/100km over 65km of driving, split between highways and country roads, so not your usual mix. A very heavy right foot definitely influenced that result, but don’t expect to do too much better in a normal run.

For reference, the GLS63’s 90L fuel tank can be filled up with 98RON petrol at a minimum.

The hardest and angriest M4 of all time is, perhaps unsurprisingly, hard and angry. This is a race track specialist, but because I don't happen to own one of those, my first experience with the barking (and barking mad) M4 CS was navigating my way back from BMW's inner-city dealership.

Like it or lump it, you're going to read some Porsche comparisons here, because you're talking not too far off base 911 Carrera money, and suddenly I find the two Germans doing battle for a spot in my dream garage.

First things first, the BMW won't be much chop for daily driving for most people. Happily, I have a sickness for uncomfortable sports cars. It tells me that no compromises have been made in the pursuit of punishing performance.

A good thing, too, because the BMW, at city speeds, can be punishing. Everything feels heavy, the seats aren't overly comfortable – especially the hard bits that tend to dig in when cornering – and it stiff-arms its way over road imperfections, that exhaust booming and barking as it does.

Again, I loved it, and you probably will, too. But it's still not the kind of car I'd relish sitting in the morning peak hour rush in.

But escape the confines of the city and the BMW M4 CS suddenly makes a whole heap of sense. The acceleration is genuinely brutal, and wonderfully theatrical, with that quad-tipped titanium exhaust barking and snarling as you rocket towards 100km/h.

The steering is brilliant, with feedback fed to your wrists via that thick-rimmed wheel, and the entire experience feels sharp, super engaging and edgy.

You can push the M4 hard and fast, and I'm certain my limited talents would run out far before the BMW's would, but there's this thrilling sense of peril sparked by the aggression of the experience, that I love.

It's like the magic of a roller-coaster, I guess. Even if you know nothing is going to happen, you never really know, right? And in that lies the magic.

But back to original question, this or a Porsche 911? There's no doubt a Carrera is a better all-rounder, in terms of comfy commuting and race track fun, but this angry M4 is all shouty theatrics, all of the time.

I bloody love it.

Frankly, the GLS63 has absolutely no right being as capable as it is. It’s a really big bus that’s legitimately convinced it’s a sports car half its size.

Being a GLS variant, the GLS63 has independent suspension consisting of four-link front and multi-link rear axles with air springs and adaptive dampers, but its party trick is the addition of active anti-roll bars.

In what feels like magic, the GLS63 is simply not intimidated by corners, despite having massive dimensions and a considerable 2555kg (kerb weight) to deal with.

The active anti-roll bars make the GLS63 so much easier to drive fast through the twisty stuff, almost eliminating body roll, taking one key variable out of the equation for the driver. Active engine mounts are also fitted, helping to settle things even further.

The electric power steering on hand is also good. It is speed-sensitive and has a variable ratio, which basically makes the set-up more direct when it needs to be. It’s typically light in hand, too, until one of the sportier drive modes is engaged and extra heft is added.

So, handling is scarcely believable, which means the ride must be compromised, right? Yes and no. With the adaptive dampers in their softest setting, the GLS63 is very compliant. In fact, we’d say it feels luxurious when compared to other high-performance SUVs.

That said, our test vehicle was fitted with the optional 23-inch alloy wheels ($3900), which look the part but expose sharp edges and other road imperfections, not to mention generate noise easily heard inside. Naturally, feedback is exacerbated in the sportier drive modes.

Anyway, there’s more performance, and the GLS63 has the rest in spades. Its engine is a powerhouse in every sense of the word. It’s so powerful, in fact, that it hilariously hunkers down off the line or when suddenly accelerating at low speed.

Thanks to the mild-hybrid system, wads of torque is available from the get-go, making for a highly responsive driving experience, even in those rare moments when the engine isn’t on song.

While not as characterful as some of the other members in the 63 series, the GLS63 still makes some thoroughly entertaining noises, with its sports exhaust system popping like mad while on the overrun.

All of this ability is very well and good, but you need to be able to pull up quickly, and the high-performance braking package (400mm front and 370mm rear discs with six-piston fixed callipers and single-pot floating stoppers respectively) mercifully does exactly that.

Neither ANCAP nor its European counterpart, Euro NCAP, have awarded the GLS range a safety rating, but it’s fair to assume it would perform well in testing.

Advanced driver-assist systems in the GLS63 extend to autonomous emergency braking with pedestrian and cyclist detection, lane-keep and steering assist (including emergency), adaptive cruise control, active blind-spot monitoring, rear cross-traffic alert, traffic sign recognition, driver attention alert, high-beam assist, tyre pressure monitoring, hill-descent control, hill-start assist, park assist, surround-view cameras and front and rear parking sensors.

Other standard safety equipment includes nine airbags (dual front, front-side, curtain and rear-side plus driver’s knee), anti-skid brakes (ABS), electronic brake-force distribution (EBD) and the usual electronic stability and traction control systems. Yep, it doesn’t leave much to be desired on the safety front.

The M4 CS is covered by BMW's five-year, unlimited-kilometre warranty, with condition-based servicing available in packs, which will cost you $3530 over five years/80,000km, or $2900 over four years/60,000km.

As with all Mercedes-AMG models, the GLS63 comes with a five-year/unlimited-kilometre warranty, which currently sets the standard for the premium market. It also comes with five years of roadside assistance.

The GLS63’s service intervals are relatively long, at every 12 months or 20,000km (whichever comes first). Better yet, it’s available with a five-year/100,000km capped-price servicing plan, but it costs $4450.