Overall rating:

As fast compact saloons go they don't get much better than Merc's C 63 AMG. Six-point-two litres of high-revving, maniac performance V8 discreetly secreted under the business-like bonnet of a subtly muscular C-Class: it adds up to one of our favourite saloon car buys. If we could afford it, that is.

Key Facts

Pricing: £55,560
Engine: 6.2-litre V8 petrol
Transmission: AMG Speedshift MCT seven-speed auto, rear-wheel drive
Body style: four-door saloon
Rivals: BMW M3, Lexus IS F, Audi S4
CO₂ emissions: 280g/km
Combined economy: 23.5mpg
Top speed: 155mph
0-62mph: 4.5 seconds
Power: 451bhp at 6,800rpm
Torque: 442lb.ft at 5,000rpm

In the Metal:

The C-Class is a fine-looking car in standard guise and AMG's visual makeover only enhances it further. Such is AMG's obsessive attention to detail the front axle's a touch further forward, while blistered wheel-arches cover the C 63's wider track. Nothing really new to write home about visually with changes limited to mildly revised headlamps and bonnet, and that's no bad thing as the C 63 has always looked just right to us - not too over the top, but confidently assertive instead.

Inside there are some useful changes, not least because the C 63 benefits from the newer interior of the rest of the Mercedes-Benz C-Class range. That means better integration of the satnav into the facia, and the entire dashboard is more sensibly and neatly laid out.

Driving it:

What's not to like? AMG's 6.2-litre V8 engine is a screamer, turning the sober-suited C-Class into a loony-tunes road rocket. It's very fast, the 4.5-second 0-62mph time not really conveying the ferocity by which the C 63 can gain speed. The key technological change over its predecessor is the adoption of AMG's wet-clutch seven-speed automatic gearbox. The torque convertor of the old car is gone and the new transmission promises faster, more decisive shifting. It offers four modes - Comfort, Sport, Sport Plus and Manual - each doing pretty much as their name suggests. Sport Plus is perhaps a bit too extreme for road use, being both too eager to hold onto revs when accelerating and too keen to create engine braking through downshifts when slowing. Likely to be useful on a track, or a particularly testing mountain road, it's actually best if you drive it yourself via the paddle-shifters.

Do so and you've pretty much complete control; only the occasional over-ruled shift is denied if you're a bit too early stabbing at the paddle. The engine remains unchanged, and really, with 451bhp, it's not exactly lacking in grunt. Or aural stimulation - the AMG V8 remaining one of the finest sounding engines you can get your hands on for under £60,000.

Also carried over is the slightly too firm suspension, which does pummel you a bit a low speeds. It's actually fine over lumpy surfaces at pace where it smoothes out the worst tarmac, but town speed discomfort is the trade-off. The steering, operated by a newly designed wheel, remains alert and decently weighted, but it'd benefit greatly from a little bit more feel through the chunky leather rim.

All-round it's quite brilliant really, unless you're averse to filling stations, as the C 63's thirst is as prodigious as its performance. Officially it'll return 23.5mpg, but it's more likely to average early teens if you're lucky.

What you get for your Money:

A supercar in a business suit. Perhaps not the most sober business suit in white as tested here, but choose a more subtle colour and the C 63 is a fairly good way of slipping your performance car under the do-gooder's radar. The C 63 more than most defines the Q car, even if its exhausts and that V8 engine do give the game away a bit. Take the £55,565 list price as a starting point, as you'll want to add a good few options to it, with AMG offering a Performance Pack and a limited-slip differential among the extras.

Worth Noting

As much as we admire the C 63 AMG saloon we'd rather have the estate. Performance estates amuse us enormously - and allow warp-speed trips to the tip.

Summary

If you're looking for big differences between the old model and the new then you'll be disappointed, though with the 'old' C 63 providing such an accomplished basis already it's hardly surprising that AMG has only undertaken a few minor tweaks in this mid-life refresh. It remains one of the most enjoyable performance saloons you can buy, and the enhancements only increase its appeal further.