Gac M8 vs Mercedes-Benz C63

What's the difference?

The GAC M8 PHEV Luxury is a people mover that carves out a very specific niche, largely thanks to its plug-in hybrid powertrain and ambitious price point. It’s undeniably well specified and genuinely luxurious inside, but it never quite escapes its chauffeur-like identity as it's a vehicle built around passenger comfort rather than driver engagement.

Being a new brand in our market limits ownership appeal, at least for now. Where the M8 really impresses, though, is efficiency, and that alone may be enough to justify its unusual positioning.

The Mercedes-AMG C 63 S Aero Edition is an absolute beast of a car, but it comes at a pretty hefty price. Yes you get a lot of performance, and the fact there are only 63 examples being made for Australia and New Zealand could be enough to get you to sign on the line. For me, though, if I was after a C 63, it’d have to be a wagon. It doesn’t need an Aero pack to look better.

The GAC M8’s design is… well, it’s out there. This isn’t a people mover that fades politely into the background. There are clear parallels with the Lexus LM, right down to the towering grille (complete with a vague hint of spindle shaping), which may well be the tallest grille I’ve encountered!

It’s a big unit, too, measuring 5212mm long, 1893mm wide and 1823mm high. The overall shape is sharply squared-off and prioritises presence over dynamism. It also comes standard with a full suite of LED exterior lighting.

The cabin claws back some design cred, though, as it’s downright plush with its semi-aniline two-tone leather upholstery - finished in a lush burgundy/black duo in our test vehicle. Accent panels vary between a diamond-design for the dashboard and doors, to suede soft-touchpoints and rose-gold inserts liberally scattered across the cabin. 

The only accent that doesn’t land is the large swathes of piano black on the centre console as it’s hard to keep clean.

There are some nice little surprises, too, like the fidget spinner-style crystal gear lever, which is surprisingly fun to fiddle with at traffic stops and two sunroofs with the rear fixed panel illuminating with internal ambient light.

Some of the finishes aren’t the best as there are joinery and door handles that don’t line up properly, which is surprisingly more annoying than you’d think once you notice it. But overall, the cabin feels well-considered and luxurious, even if the execution isn't always flawless. 

I’ve never been the biggest fan of the current C-Class Coupe’s styling. To me, it has always looked a little droopy, a little melted at the back. 

I have to say, the Aero Edition has changed my opinion somewhat, as the new graphic elements help lift it up a bit, visually raising its rear up like a stretching cat, tail in the air. I’m still not 100 per cent on it, but to my eye it’s better.

The carbon-fibre trim elements that have been added to the exterior certainly add some menace to the look, too, and I simply can’t help but constantly notice out of the corner of my eye the AMG pressing in the staggered, dished rims. At a glimpse, from a distance,  it looks like rim damage, but thankfully it’s not!

The staggered set-up does really add some width and mongrel to the look, as if it needed more, with its open maw lower bumper air dam, and the signature 'Panamericana' grille treatment which looks like an evil character out of a movie. If you know the one I’m talking about, let me know in the comments.

As much as the look matters when it’s parked in your driveway, it’s the cabin that arguably matters more, right? That’s where you spend your time, after all. Check out the interior images to see if you think it lives up to the exterior look.

The front row has plenty of space and the seats feature heating and ventilation, making longer journeys comfortable. However, there’s no extendable under-knee support and only the driver gets lumbar adjustment. I’ve spent much of the week feeling like a chauffeur, as my husband and child insisted on sitting in the back!

The middle row is where the M8 really shines. The captain’s chairs are indulgent, offering full recline, footrests, heating, ventilation, and massage. Comfort is excellent, though the footrest extension limits space for the third row, and even at 168cm I found it a snug fit when fully reclined. Access is straightforward with grab handles and a low 143mm step-in height, though be mindful of kerbs as the doors aren’t forgiving when it comes to tall council strips.

The third row is one of the few that genuinely accommodates adults. Head- and legroom are ample, and the seats feel firm but comfortable, especially with the foldable armrest. Amenities aren't forgotten with four cupholders, two USB-A ports and directional air vents. Access requires sliding through the middle row, so it’s best if those seats are unoccupied, but otherwise it’s not too taxing.

Front-row storage is practical, with a mid-sized glove box, dual-opening middle console, cupholders and a clever phone cradle that integrates a wireless charging pad and cable routing for a tidy set-up. There’s also a USB-A and USB-C port and a 12-volt socket in the large shelf underneath the centre console.

The middle row enjoys three USB-A ports, a USB-C port, directional air vents, retractable sunblinds, tray tables (though not usable while driving) and climate control. Storage is decent, with six cupholders, one of which has heating and cooling, two map pockets, a pull-out drawer and a 220-volt AC outlet.

The 10.1-inch touchscreen multimedia system is serviceable but feels slightly small for the luxury segment. Graphics aren’t the sharpest, the layout isn’t always intuitive and some functions, like the heated steering wheel, require digging through menus. Wireless Apple CarPlay and Android Auto performed flawlessly throughout the week and the 12.3-inch digital instrument cluster is clear and well laid out.

Boot space is modest for a people mover, offering 280L with all rows in place which is enough for a small grocery run but not for a fully-loaded family outing. Folding the third row expands capacity to 1500L, though that leaves you with a four-seater. The loading height is low, which helps, but it has a tall lip which prevents it from being ideal for sitting on during tailgates or picnics. There’s a small underfloor compartment housing the tyre repair kit and a powered tailgate rounds out the package.

No two-door coupe is going to offer you the space and comfort of a sedan or wagon, that’s just a fact. But that only matters if you plan to actually use the rear seats. If you don’t, then the Coupe version of the C 63 S might be perfect for you.

Even so, I managed to (only just) squeeze myself between the seat and the door opening to slide into the rear row. This won’t be easily achieved by all attempters, especially on the driver’s side.

Let’s just say I probably looked like I was doing something very weird to the driver’s seat as I spider-manned my way in. 

The rear space is tight for someone my height (182cm/6’0”) behind their own driving position, with knees hard-up against the seat in front and not much headroom (my noggin’ was brushing the ceiling) or toe space (size 12s don’t fit so well) to speak of.

It’s certainly a selfish car. Or maybe it’d be fine for smaller kids. There are two spaces in the back, both with ISOFIX child seat anchors and top-tether points.

But there is storage in the back - cupholders and storage caddies either side of the seats, though the storage situation improves in the front zone, with bottle holders in the doors, cupholders between the seats, loose item storage under the media screen and a covered centre armrest bin, too.

The front cabin is a special looking place, with carbon-fibre abounding across the dash and nice trim on the doors. The AMG steering wheel is a sight to behold - it’s a flat-bottomed unit with carbon-fibre and Dinamica (that’s Benz talk for microsuede) trim: perfect for sapping sweat as you manhandle the C63 through the bends.

The seats are AMG Performance sports units up front, and the trim used is reserved for this model specifically: Nappa leather with yellow stripes. There are yellow details elsewhere, including on the rear seats, centre console and dash, and it certainly adds some visual excitement.

Media is controlled by a 10.25-inch display and Mercedes-Benz’s touchpad control system, but there is no touchscreen - rendering the Apple CarPlay and Android Auto smartphone mirroring technology somewhat tedious.

I’ve always had a gripe with screens that don’t allow touch but feature the tech that’s designed to transfer your phone’s screen to the media unit, and I can tell you the longer you spend twiddling the dial to get where you want to go, the more annoying it becomes.

The Burmester sound system has 13 speakers and is rather good, but I prefer the sound from the standard fit variable sports exhaust. So maybe that quibble with CarPlay isn’t that big a deal.

And if you just want to charge your phone, and there’s a second USB port up front, as well. Note: in non-Aero Edition C 63 models without the carbon-fibre interior pack, you also get Qi wireless phone charging, but it’s deleted from this variant and any model with the carbon pack.

The driver has a 12.3-inch digital info display to show where you are and what the car is up to, and there’s a head-up display as well. Yep, there’s standard sat nav with live traffic updates (and even live fuel price updates) - it’s just a shame the maps still look early 2000s-spec in 2D layout.

Cargo space is okay. The claimed cargo capacity or boot volume is 355 litres (VDA) with the rear seats in place. That’s small for a coupe of this size, and the shape of the boot (with a hump behind the rear seat) isn’t great as things do move around quite a bit.

But, thankfully, Mercedes has included its clever foldable storage box system under the boot floor - it goes where you might usually expect a spare wheel, but there isn’t one in this car. Instead you get Mercedes’ 'Tirefit' repair kit with an electric pump.

Look, I’m not likely to ever be in the position to say that a car that costs $188,600 plus on-road costs is “good value”, but to be honest, if you’re in that position, you’ll be getting plenty of car for your cash.

The Carbon Edition of the C 63 S Coupe adds $17,200 over the standard version of the high-performance two-door, but it adds a bunch of extras to help justify its price. A car like this is always going to be seen by some as a profligate purchase, right? You need to be able to justify spending an extra MG3’s worth of cash on this Edition. 

The noticeable exterior bits include an AMG Performance rear spoiler, a model specific front lip, rear diffuser, and side facings for the rear apron air vents. Carbon-fibre is used in the front apron A-wing, the side sill inserts, rear diffuser insert, rear spoiler and the side mirror casings. 

There’s more carbon-fibre inside the cabin, which we’ll cover off in the interior section. Other additions over the standard C 63 S Coupe include ceramic composite front brakes (402mm six-piston) and 360mm single-piston rear brakes, and there are “ultra-lightweight” AMG forged 'Matt Black' alloy wheels with 19-inch rims at the front and 20s at the rear. 

And in nice news, the car you see here has no optional extras fitted at all. The colour is 'Iridium Silver', one of only two options for this limited run model (the other available hue is Polar White, and both come at no extra cost).

Standard inclusions comprise leather interior trim, heated and electric adjustable front seats, dual-zone climate control, a 10.25-inch media screen with sat nav and smartphone mirroring, DAB radio, 13-speaker Burmester sound system, 12.3-inch digital driver info display, head-up display (HUD), ambient lighting, and performance items like active dynamic engine mounts, an adaptive AMG performance exhaust, a rear differential lock, and adaptive sports suspension.

Plus there’s a full-spec safety offering which we’ll cover in the section below.

Thinking about what cars compete with this one? There’s the Audi RS 5 Coupe (from $150,900), the Lexus RC F (from $136,636), and the BMW M4 Competition (from $167,829). So the C 63 S - which is already expensive comparatively - looks positively pricey in Aero Edition spec.

Both M8 grades share the same plug-in hybrid powertrain, pairing a 2.0L, four-cylinder, turbo-petrol engine with a single electric motor. Combined, they produce up to 274kW of power and 630Nm of torque which is impressive on paper, though it only manages 0‑100km/h in 8.8 seconds. Once the battery is depleted, outputs drop to a more modest 140kW/320Nm. Power is sent to the front wheels through a two-speed automatic transmission, and the M8 is not rated for towing.

To get the best performance from this type of set-up will require diligent recharging.

Open the shapely bonnet of the C 63 S and you’ll find a hand-assembled horsepower-monster engine with a printed name plaque to prove it.

The 4.0-litre twin-turbo V8 produces 375kW of power at 6250rpm, and 700Nm of torque from 2000-4500rpm. It runs a standard-fit nine-speed 'Speedshift MCT' (multi-clutch transmission) automatic, and it’s rear-wheel drive. And yes, that means it likes to boogie.

The claimed 0-100km/h time is just 3.9 seconds, and top speed is apparently pegged at 250km/h. Yeesh.

The name on the “Handcrafted by” plaque on this particular engine? Hat tip to you, Julian Rembold. This is quite a piece of work. 

The M8 is equipped with a Type 2 CCS charging port, accepting up to 6.6kW on AC and 39kW on fast DC power. Being able to use a DC charger is a definite plus for a plug-in hybrid and you can charge the battery on this type of charger from zero to 80 per cent in around 30 minutes.

Its 25.57kWh lithium-ion battery is generous for a plug-in, delivering an electric-only range of up to 106km (WTLP). With a combined cycle (urban/extra-urban) fuel consumption figure of 6.1L/100km and a 56L fuel tank, the M8 offers an overall driving range of more than 1000km which is excellent for a vehicle of its size. As with any plug-in, regular charging is key to achieving these figures; over my week of driving, I averaged 6.2L/100km, which is very excellent.

GAC recommends a minimum 91 RON unleaded petrol.

High numbers are what AMGs are about. Sadly that’s the case not only for performance outputs but also fuel consumption.

The official combined cycle fuel use claim for the C 63 S Coupe is 10.3 litres per 100 kilometres, and you need to fill it with 98RON premium unleaded fuel, too.

On test? Well, across a mix of different driving - urban, highway, back road and spirited stints - I saw an 'at the pump' return of 12.2L/100km, while the digital readout stated 12.0L/100km.

Given the performance on offer, and how much I took advantage of it during my week with the car, that’s not bad…

Fuel tank capacity is 66 litres. So go easy if you know there won’t be a fuel stop for a while.

Around town, the M8 delivers plenty of power and is whisper-quiet when running in electric mode. Once the battery depletes or you switch over to the petrol engine, that sense of instant oomph fades. Overtaking on hills is achievable, but even with an empty car it can feel a little underwhelming.

Steering is light, but the car feels solidly planted in most situations. Handling isn’t as dynamic as a Kia Carnival and the M8 can feel a touch ungainly through bends, though it’s more than manageable for everyday driving.

Ride comfort is high, especially for passengers, due to forgiving suspension and a cabin that doesn't let a whole lot of road or wind noise in. The M8 is a comfortable cruiser.

Visibility is surprisingly good for a 5.2m-long vehicle with minimal blind spots from the driver’s seat. The bonnet and dash, however, stretch further than they appear, which can make judging the nose a little tricky at first.

Ground clearance is only 143mm, so it’s easy to scrape the nose over speed bumps or when parking. The 360-degree camera system is decent, but manoeuvring into tight spaces still requires some care as it fills out a space. You also have to leave about a metre of clearance behind you if you want to open the tailgate.

Just one word sprang to my mind when it comes to accurately describing the performance on offer from this car. The word is ‘brutal’.

Smash the accelerator and the power and torque on offer is enough to make your eyes feel like they’re not doing the right thing anymore. You get pushed back in your seat with a surge, and your ears are also rewarded with one of the best soundtracks in the automotive world. 

The engine builds pace with enormous intent, and the sound that comes from under the bonnet and out the back through the exhausts is addictive.

Yes, there is an active exhaust button which you have to press to make sure that you hear all that noise if you’re running around in 'Comfort' mode, and during my time with the car it was active the whole time.

I had some questions from neighbours over the week that I had this car about whether it was actually nice to live with on a day-to-day basis. And the answer is yes, if you put it in comfort mode it’s surprisingly amenable. 

The ride is really well sorted at pace despite having a bit of that trademark low-speed wobble that seems to afflict Mercedes products from A-Class through to the GLE SUV. But it wasn’t bad enough to really bother me, as most of my time was on highways and backroads.

The steering is direct and accurate. The only thing you need to be aware of is that you will lose traction at the rear axle when you put your foot down hard. And for the enthusiast that’s exactly what you want. 

I know I want to feel the thing squirm under throttle. It’s a rear-drive V8 coupe, after all. You want to feel like you’re a vein in its bicep muscle; you know, the one you see in a weightlifter’s arms – the one that wiggles around a lot. You want to have that. Right?

On the performance front it is exceptional. Twist the little dial on the wheel to 'Sport' or 'Sport+' (I didn’t sample 'Race' mode as I wasn’t at a racetrack), and everything feels like it’s had a protein shake.

Even so, in that mode it steers brilliantly, there's a nice feel through the wheel, and the ride, while stiff, controls the body brilliantly when you change directions. 

The transmission is very good, too. In Comfort mode it can take just a second or two at first to become accustomed to the idea that you want to drive aggressively.

But in Sport mode, or when you select the manual transmission mode using the trigger button on the steering wheel, you will certainly get the most out of the engine. That’s what I did when I was driving it in a ‘spirited’ manner.

If you are just after that high-end Coupe cruiser experience, it’s a relatively quiet car (provided the surface below isn’t the coarsest of coarse-chip bitumen), with enough luxuriousness to make it feel premium as well as sporty. That’s an important thing to consider, especially at this price point.

There is no applicable ANCAP crash test rating for the Mercedes C-Class Coupe, nor is there one for the C 63 specification. But when it was tested back 2014, the sedan scored five stars - as you’d expect.

It is comprehensively equipped in terms of safety technology, including auto emergency braking (AEB) with pedestrian and cyclist detection (from 7.0km/h to 70km/h) and it’s active for cars from 7.0km/h to 250km/h.

Plus there’s lane departure warning and active lane keeping assistance (from 60km/h to 200km/h), blind spot monitoring with 'Active Blind Spot Assist' that will stop you from veering into oncoming traffic, front and rear cross traffic alert, and adaptive cruise control (Distronic) with traffic jam assist.

The C 63 also features 'Route Based Speed Adaptation', which can adjust your speed based on where the car thinks you are on the map. Just note - if you’re driving through new tunnels that haven’t been flashed to your car’s nav (as happened to me in Sydney during my testing week) - then you could find the car dramatically braking for surface-level intersections. You can switch the system off, thankfully.

There are nine airbags fitted, and while you mightn’t use the rear seats much there are ISOFIX and top tether points for both positions (yes, only two).

The GAC M8 is backed by a seven-year, unlimited-kilometre warranty, along with five years' complimentary roadside assistance, which is competitive against several of its nearest rivals. Service pricing has yet to be confirmed, though servicing is scheduled at 12-month or 15,000km intervals.

For now, the service network is limited, with around 10 centres nationwide, though GAC offers authorised servicing through third-party providers such as MyCar, which helps broaden access in the short term.

Mercedes-Benz is among the minority of luxury brands now offering a five-year/unlimited kilometre warranty plan - most still have three-year cover. So that’s a tick.

And the service intervals are pegged at 12 months/20,000km. Another tick.

Plus you can either pre-pay your service plan in three-year ($3800), four-year ($6000) or five-year ($6550) plans - roll it into the finance package, and it won’t hurt quite as much.

According to Mercedes, the three-year coverage option makes for a $900 discount over pay-as-you-go servicing.

Roadside assistance covers the five-year new car warranty period, too. So Mercedes seemingly takes good care of its customers. But if you have any concerns or questions over reliability, problems, issues or complaints about the C 63, check out our AMG C 63 problems page.