BMW M Models vs Mercedes-Benz G63

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 Mercedes-AMG G 63 isn't for shrinking violets. It's bold, fast, and loud, and in second-generation form massively improved dynamically and technically. It's a lot of money, but there's a lot to love, and here's hoping it stays around for decades to come.

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.

The original (W460) G-Glass, then known as the G-Wagen (or Geländewagen for cross-country vehicle), was launched in 1979 as an ultra-capable off-roader, soon favoured by armies the world over. Arriving here in 1982, its distinctive, slab-sided form remained unchanged over the best part of four decades.

At close to 4.8m nose-to-tail, more than 1.8m across, and a bit over 1.9m tall, the G 63 is now longer (+110mm), wider (+106mm), and fractionally lower overall (-13mm), but still pulls off a convincing impersonation of a bread box.

Merc-AMG confidently quotes a drag coefficient (Cd) of 0.55 for the G 63, which isn't as bad as a brick (around 2.0… I Googled it) although it is in the same league as a heavy truck.

But it's the car's unique, upright stance, complete with pumped wheelarches and old-school flat glass, that sets it apart and draws people in. Looking more like a take-no-prisoners, functional device than a luxury cruiser, I can assure you it attracts as many admiring looks and comments as a low-flying supercar wedge.

The new-gen G 63 features AMG's vertically slatted 'Panamericana' grille, and our test example was fitted with the optional 'Night Package' ($5900) adding a range of dark exterior details including tinted indicator lenses, dark tinted glass, black exterior mirror shells and spare wheel ring, other black trim pieces and painted areas, as well as 22-inch AMG forged alloy rims.

Also worth noting, Merc has retained the G-Class's solid metal door handles, complete with the mechanism's unmistakable 'click-clack' opening and closing sound. Nice touch.

Inside, the biggest change is the upgrade from a conventional dual-gauge instrument cluster and central media stack to a pair of 12.3-inch digital screens, forming a sleek widescreen display, and bringing the G 63 in line with other recent Merc offerings.

Similarly, the gearshift moves from a traditional console-mounted set-up to Merc's 'Direct Select' lever on the steering column (exactly where the indicator stalk is located in 90 per cent of right-hand drive cars).  And the standard flat-bottom, leather-trimmed 'AMG Performance' steering wheel is a racy addition.

Like the exterior door handles, another tip of the hat to the car's heritage is retention of the horizontal grab handle ahead of the front passenger on the dash above the glove box. Nice to have something to hold on to if the going gets rough.

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.

The G-Class has never been a particularly squeezy proposition for passengers or cargo, but an extra 40mm in the wheelbase adds even more breathing space.

Getting in is the first step, and it's a big one. At 183cm tall, in an athletic mood, I could grab the A-pillar and swing up into the driver's seat in one vaguely respectable movement.

But, those side steps aren't just for show, and at the end of a long day provide a handy staging camp between terra firma and the lofty pilot's chair.

Once on-board there's plenty of room up front, with adequate storage including a bin between the seats (now with a double door opening rather than a single hinged lid), a modest glove box, oddments space and two cupholders in the centre console, and bins with space for bottles in the doors.

There's a 12-volt power outlet in the front, second row and cargo area, while there are two USB ports in the centre console bin and a charging USB port in the second row.

In the back I could have donned a dusty Akubra and still had headroom to spare, with generous foot room, and a substantial gap between my knees and the driver's seat (set to my position).

A fold-down armrest incorporates a pair of cupholders (as well as a through-port to the cargo space for long items) and there are map pockets on the front seat backs as well as space for bottles in the doors. Two adjustable air vents in the rear of the front centre console, and another pair in the B-pillars also provide climate-controlled air to those in the rear.

With the rear seats upright boot volume is quoted at 454 litres (VDA); enough to easily swallow our three-piece hard suitcase set (35, 68 and 105 litres) or the CarsGuide pram, or a largest-suitcase-and-pram combo.

There are tie-down shackles in each corner of the floor, usefully bright lighting, a netted storage area on the passenger side (containing five fluorescent emergency vests), and folding the 60/40 split rear seat liberates even more space.

Unfortunately, gaining access to that load space is fraught with compromise. First, the single-piece rear door hinges vertically and opens from right to left. No problem when you've nosed into a shopping centre space, but not so great when you're parking nose-to-tail on the left-hand side of the road.

That means you typically have a small space between you and the car behind to get the door open, and when it is at 90 degrees, you're blocked from unloading things onto the footpath until you've shut the door.

As well as that, the door has a full-size spare (alloy) wheel and tyre attached to it. Good because a full-size spare is welcome, and bad because it makes the already bulky door even heavier.

Those keen on towing things will be pleased to hear the G 63 is rated to haul up to 3.5 tonnes of braked trailer and 750kg unbraked.

Okay, you're laying down a quarter of a million bucks ($247,329 before on-road costs) and it's fair to expect some serious tech and standard equipment to keep you feeling warm and fuzzy after you're finished impressing friends and family with the G 63's howling acceleration.

For a start, there's a bunch of leading-edge safety tech on-board (detailed in the safety section below), and as expected that substantial cost-of-entry brings an extensive list of luxury features.

We've touched on the twin 12.3-inch 'Widescreen Cockpit', and available media includes digital radio and TV tuner, internet connectivity and 3D nav (with dynamic route guidance), as well as smartphone integration with Apple CarPlay and Android Auto.

Audio is a thumping 15-speaker, and 590-watt Burmester surround sound system, and the ambient lighting set-up offers a choice of 64 colours.

Also included are 'Multibeam' LED headlights, 'AMG Ride Control' adaptive damping, a 'Parking Package' with 'Active Parking Assist' and 360 camera, a sliding glass sunroof (with tilt function), the selectable AMG sports exhaust system, keyless entry and start, the AMG Performance steering wheel (trimmed in nappa leather), and 21-inch AMG '5-Twin spoke' alloy wheels.

Then there are the three 100 per cent differential locks (plus an 'off-road information centre'), electronically adjustable front seats (ventilated front and heated front and outer rear), steering column and mirrors (with memory function), three-zone climate control, nappa leather upholstery, a leather-finished dashboard with open-pore ash wood trim, a 'Dinamica' microfibre roof liner, and an AMG-specific IWC design analogue clock. Plus, the 'Dynamic Select' system enables a choice of pre-set driving profiles or individual settings.

The optional 'Exclusive Interior Plus Package' ($10,300) fitted to 'our' car adds deluxe nappa hide on the dashboard, door centre panels and grab handle, as well as a diamond quilted treatment on the seat centres, a black 'Dinamica' roof liner, velour floor mats (with edging in nappa leather), a frameless interior mirror and air vents in 'Silvershadow'.

On top of that the test vehicle was optioned with the 'Night Package' ($5900) detailed in the Design section, and Designo 'diamond white bright' paint ($5900) for a manufacturer's recommended list price (MRLP) of $269,429.

That puts the G 63 in the same price and equipment ballpark as the supercharged V8 Range Rover Autobiography ($268,900), twin-turbo V8 Porsche Cayenne Turbo ($239,400), and its Mercedes-AMG GLS 63 sibling ($221,729), powered by a version of the 5.5-litre twin-turbo V8 used in the first-gen G 63.

An impressive trio of alternatives, but in reality the idiosyncratic G 63 doesn't have any direct competitors, and for those who give in to the pull of its powerful tractor beams value-for-money becomes a uniquely personal concept.

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 G 63's 4.0-litre (M177) all-alloy V8 is closed deck design using direct-injection and a pair of twin-scroll turbos to produce 430kW at 6000rpm and no less than 850Nm from 2500-3500rpm. That's 10kW/90Nm more than the 5.5-litre twin-turbo V8 it replaces!

To improve throttle response and optimise efficiency, the turbos are located inside the engine's 'V', improving air flow and shortening the distance from the exhaust side to the turbos, and in turn, from the turbos to the inlet side.

And the housings on the twin-scroll turbos are divided into two parallel flow channels connecting with separate ducts in the exhaust manifold, allowing fine management of the exhaust gas coming in and pressure going out. Result is more torque and even better response times.

Drive goes to all four wheels via a new 'AMG Speedshift' nine-speed, dual-clutch auto (replacing the previous seven-speed auto transmission) with paddle shifters and a multiple downshift function which will go to the lowest ratio possible as you keep squeezing the shift paddle.

The 'AMG Performance 4Matic' all wheel drive system is front/rear biased 40/60 (50/50 in the previous model), although if you want to head off-highway the G 63 still features three 100 per cent diff locks and low-range off-road gear reduction.

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.

Claimed fuel economy for the combined (ADR 81/02 - urban, extra-urban) cycle is 13.1L/100km, with the 4.0-litre, twin-turbo V8 emitting 299g/km of CO2 in the process.

Despite the fact cylinder management tech means the engine will run on four cylinders under light load, and start-stop (with 'glide mode') is standard, we managed 16.7L/100km (measured at the bowser) over a mix of city, suburban and freeway running. To be expected for such a big bus, especially one that constantly tempts you into squeezing the throttle just to hear the exhaust bellow.

Minimum fuel requirement is 98 RON premium unleaded, and you'll need 100 litres of it to fill the tank.

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.

Let's cut to the chase. The G 63's pure grunt overpowers its challenging aero profile to thrust this boom box on wheels from 0-100km/h in a claimed 4.5 seconds. And believe it or not, despite its greater length and width, it has enough power to punch a 240km/h hole in the air (maximum velocity is limited to 220km/h if you choose not to opt for the 'AMG Driver's Package').

The new electronic architecture brings with it the latest version of Merc's 'Dynamic Select' system with five driving modes adjusting the engine, transmission, suspension, steering and assistance systems right up to maximum attack Sport+ mode.

All 850Nm of peak torque is available between 2500-3500rpm and pinning the throttle anywhere in that band feels like lining up a runway and preparing to rotate for take-off.

The two-stage exhaust flap arrangement allows you to turn the noise up from growl to roar even at modest around town speeds, and the nine-speed transmission is sharp and positive, with the multiple downshift function (in manual mode) hilariously good fun.

The racy AMG sports seats are as grippy as they are comfortable, and the fat 295/40 Goodyear Eagle F1 rubber, wrapped around the optional 22-inch forged alloys, does a good job of keeping all that mass and momentum in control as the high riding G 63 careens around corners.

And speaking of mass, the job of hauling it from warp speed to rest sits with big ventilated discs all around (cross-drilled 400mm front/370mm rear), clamped by monster six piston calipers at the front and single piston at the back. They're progressive and reassuringly powerful.

So, the performance is as dramatic as ever, but when I think of previous Merc-AMG G-Class offerings, two main shortcomings come to mind... steering and ride.

The steering was like a laggy mouse, with a few beats separating input at the wheel from response at the front treads. And the damping came up short, with a bouncy ride par for the course.

Still sitting on a ladder-type frame, the new G's suspension was developed by Mercedes-Benz and Mercedes-AMG. And finally, it has a decent double-wishbone independent front-end, with a rigid axle at the rear and coil springs all around. Plus, a strut tower brace, Merc-AMG calls it a 'suspension bridge', now connects the front strut towers, increasing torsional rigidity.

Ride comfort, especially in the most compliant 'Ride Control' suspension setting and riding on the big 22s, is massively better. It's no limo. You'll still feel jittering over higher frequency imperfections. But it's way, way ahead of the first-gen version.

The steering system changes from a recirculating ball to rack and pinion, and is now variable ratio with electro-mechanical rather than purely hydraulic assistance. And it's also much improved. We're not talking about a Lotus Elise-style connection with the road, but the steering is clearly more predictable and responsive.

One thing that hasn't changed is an ocean liner-worthy, 13.6m turning circle. You'll need to plan ahead for U-turns and reverse parks, but enough parking cameras (including surround view) to please Cecil B DeMille are on hand to help.

It's like a whole new world with a familiar cover wrapped around a markedly improved package. But (there must be a but) visibility is still compromised by thick window and door pillars, and despite the new dash layout ergonomic efficiency is patchy, with some switches and knobs located in relatively awkward positions.

As mentioned earlier the G 63 features three 100 per cent diff locks and low-range off-road gear reduction. But forget breakover angles and wading depths. This 4x4 seeing off-road action is as likely as an Abbott 2.0 prime ministership.

Suffice it to say, this car wears the 'Schöckl' badge at the base of its B-pillar. And in case you were wondering, Schöckl is a 1445m mountain in Graz, the Austrian city where the G-Class is built (and big Arnie Schwarzenegger was born!).

In the second-gen G-Class's development, prototypes covered roughly 2000km over a five kay trail including gradients of up to 60 per cent and lateral inclines up to 40 per cent. So, despite its irrelevance, the off-highway box is ticked.

The second-gen G 63 hasn't been assessed by ANCAP or Euro NCAP but its new electronic architecture brings the car up to speed on active safety tech, now incorporating 'Distronic' cruise control with 'Active Distance Assist', 'Active Brake Assist', AEB (forward and reverse), 'Active Lane Keeping Assist', 'Blind Spot Assist', 'Adaptive High-Beam Assist', tyre pressure monitoring, and 'Traffic Sign Assist'. Plus, the 'Pre-Safe' system prepares the vehicle and occupants in the face of an inevitable collision.

And once that impact has occurred, you're protected by nine airbags, including rear seat airbags, full-length curtains and a driver's knee bag.

There are three top tether points for child restraints/seats across the back seat, with ISOFIX anchors in the two outer positions.

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.

Mercedes-Benz (and by extension Mercedes-AMG) offers a three-year/unlimited km warranty with 24 hour 'Road Care' emergency roadside assistance provide for three years.

Servicing is recommended every 12 months/20,000km and a capped price servicing plan is available at Silver and Platinum levels for up to five years/100,000km.