What are you driving?
This is the updated Mercedes GLC in its somewhat controversial 'Coupe' form, that takes the standard bodyshell and knocks a big chunk out of the rear bodywork to create a more sloping, fastback, roofline. Fashionable? Certainly, but we've always been a bit unsure of this corner of current vehicle design. After all, when the standard GLC is as handsome as it is, why would you make an uglier, less practical version and charge more for it? Because people will pay for it, we guess...
This, though, is the most convincing Coupe version of the GLC because it's not a Mercedes-Benz, it's a Mercedes-AMG and the insanity-merchants from Affalterbach have shoehorned in the mighty 4.0-litre twin-turbo V8 engine from the C 63, E 63 and so many others. Here, it's in 510hp 63 S trim, with 700Nm of torque, driving all four wheels through Mercedes' nine-speed automatic gearbox and 4Matic+ all-wheel drive.
In terms of newness, the GLC 63 gets a similar round of updates as the standard car - new grille (here in the AMG-specific 'Panamericana' style with thick, vertical slats), new lights (all-LED all-round now), new paint options (including a rather smart graphite grey) and a new 21-inch alloy wheel option.
The cabin gets the same new digital instrument cluster and bigger MBUX infotainment setup, but for the 63 there are AMG-specific digital instrument graphics. You also get muscular-looking high-backed bucket seats clad in Merc's oddly satisfying 'Artico' artificial leather.
On the technical front, the GLC 63 S now gets a standard electronically controlled locking rear differential, special AMG air suspension with adaptive dampers and an extra layer to the Dynamic Select function. As well as adding both Slippery and Race modes to the usual Comfort, Sport and Sport +, there's also another set of AMG-specific levels-within-levels, which go Basic, Advanced, Pro and (for the S model only) Master. Basically, it means you can tweak and adjust the levels of driver assistance and electronic safety nets to suit your mood, the weather and the fear levels of your passengers. There's even a track-map mode in the Race setting that can project cornering lines and braking points for well-known racetracks onto the head-up display.
Name its best bits
Well, if you really must buy a GLC Coupe, then this is the one to have, as it's the best-looking by far. The extra protein-bulk of the AMG body kit, the 21-inch wheels and the delectable duck's arse carbon-fibre spoiler at the back really sharpen up a shape that, in basic form, looks a little too amorphous and blobby for our liking.
Then there's the engine. This 4.0-litre V8 just never seems to get old. It's as bombastic and noisy as you want it to be (literally, as there's an electronically controlled sports exhaust) yet it's not the complete nutter you might expect. Twiddle the Dynamic Select switch to Comfort and loaf along at the legal limit and it's refined, buttery-smooth and not even all that thirsty (well, relatively so anyway). Even in Comfort there's no doubting its sheer potency though, and on give-and-take country roads, Comfort is arguably the best setting, as the ride just starts to get too busy in Sport. You don't need to select Sport, really you don't. Or Sport +. Seriously you don't...
It's just too tempting though. Too tempting to use the delightfully tactile little rotary switch dangling from the spoke of the Alcantara-clad steering wheel and twist it until you get Race mode up. Then the suspension becomes all-but unyielding, but your back will forgive you because your ears will be so entertained. Race unleashes the full Van Halen backing track of malevolent growls, yells and overrun crackles. A 3.8-second 0-100km/h time doesn't even begin to tell you how fast this car actually feels, and if its weight does blunt performance ever so slightly compared to the C-Class saloon, Coupe, or estate with which it shares so much, then the tractive abilities of the 4Matic system compensate, propelling you out of corners like a shell from a howitzer, with an occasional little wiggle from the rear as that electronic differential comes out to play.
The steering feel is excellent (why can't Mercedes just fit this rack to the standard car?) and while you do have to account for the sheer weight and bulk of the GLC, it's astonishingly agile on a country road for a car such as this.
And then you get it to a derestricted section of the Autobahn and start to put that 280km/h electronic limiter to good use. The way the GLC 63 S gathers speed is really quite something, even when you're used to driving high-performance cars. Not especially socially responsible, but hey, it's hard not to be tempted when the Devil sings this sweetly...
Anything that bugs you?
Well, if the economy and emissions figures don't make you choke on your tea, then you clearly haven't been listening to David Attenborough of late. Aside from that, the boot is smaller than that of the standard GLC 63 S (which comes with all the same V8 engine and suspension) and that ride quality, even in Comfort mode, might be a bit too stiff for Irish conditions. And there's always the lingering feeling that you'd be having more fun in the C-Class with the same engine.
And why have you given it this rating?
If you don't fall more or less instantly in love with a car packing an AMG V8 then you can't really call yourself a petrolhead. The GLC 63 S has theatrical performance, operatic noise and balletic poise, and while we certainly have reservations over the body shape, the profligacy and the social responsibility, it's still a barn-storming all-rounder.