needs to be very good. Sounds blunt, but consider it this way: the RS4 arguably hasn't been the pick of this sector for a decade now, since the departure of the B7 generation. The
has shown a degree of Audi Sport panache, though is approaching the end of its tenure - there's no escaping that an
is a more complete car now. And
, talented and accomplished though it is, struggles to charm against familiar German (and less familiar Japanese) rivals.
More than that, however, is the very fact that this is Audi heartland; more than the huge wagons, more than the R8 and arguably more than anything with five cylinders, doing compact and potent estates is the foundation on which the Audi Sport legend resides. The RS2 was like nothing else at the time; the first RS4 was within 20hp of a Ferrari which cost twice as much; the B7 RS4 was the first fast Audi anybody could quite happily buy over an M3. There's heritage, put simply, heritage that Audi will be only too aware of and keen to add to.
However, there's competition, too; limited in scope, yes, with the focus currently on uber SUVs rather than their estate counterparts, yet no less formidable. The Mercedes-AMG C63 picked up in 2015 where its predecessor had left off in spectacular fashion: a more serious prospect, certainly, yet still offering a compelling blend of V8 muscle, rear-drive hooliganism and haul-the-family practicality.
might well sit in the shadow of its four-wheel drive senior at present, but it remains a sensational fast estate. That begins even before you've moved an inch: the front negative camber is plain to see, the V8 awakens viciously and a prod of the throttle rocks the car gently. Family estate or not, this feels an intimidating, very naughty car.
Yet it's not scary, even in January with single-digit temperatures on the display. In fact your first thought - tough ride notwithstanding - is what a big charmer this 510hp, rear-wheel drive car is. It rumbles along purposefully below 3,000rpm as the fluids come up to temp, the throttle response is great and the steering is good, if not a patch on the old hydraulic system.
Playing the V8 cruiser has never been an AMG problem however; what's transformed for this latest generation, and thrown into the starkest light on a cold and dark Monday morning, is just how good they are as driver's cars. There's precision, accuracy and confidence you simply wouldn't credit the car with, an ability to deliver and entertain on a B-road that even AMGs of a generation ago didn't have.
Because the damping is so assured, the car so composed and the reactions so instant, you have faith to push even in grimy conditions. The wheels will spin if you're greedy, though so well telegraphed is the slip and so well calibrated is the traction control that you can embrace it rather than be afraid of it. The C63 can be as sensible or as silly as you like, which makes it outrageously appealing even on a limited test. You want a true multi-purpose vehicle, a car for every scenario? This might be it.
By the time Nic arrives with the RS4, the C63 feels near-invincible. January really shouldn't suit it, yet the way it's embraced the conditions without feeling diluted or dim-witted really is some achievement.
Even in a spec that doesn't especially suit it, the RS4 does the fast estate aesthetic very well. The arches are appropriately blistered, the wheels fill them just so, and there's just enough to look out for that identifies this as not just another A4. Let's call it a score-draw on the styling front; it's the best spec of C63 we've seen, and the least desirable of RS4, so there isn't a clear victor.
Other elements of the car should come as no surprise: the interior is very nice, the materials are lovely and the driving position is spot on, too, probably better (for being lower) than the Mercedes. It sets the right tone, which a slightly contrived V6 gargle only ebbs away slightly at.
There's no doubting the effectiveness of those six cylinders, two turbos and 2,891 cubic centimetres, though. It feels even more urgent than the C63 at low revs, eager and keen to get going while the Mercedes takes the most momentary of pauses. The Audi's automatic gearbox feel a fraction sharper to up and downshift also. The key numbers might be lower, but the RS4's performance is never in doubt.
You know there's a 'but' coming, don't you? Put simply the C63's powertrain remains more of an event: it's the better sounding, the more powerful, the more entertaining. The Audi is frantic and fast, but far less memorable.
The same applies for the rest of the driving experience, sadly. There's no doubting the effectiveness or the ability of the Audi RS4, but there are issues with how much you might enjoy it. Nothing will be faster down a road (apart from maybe an RS6), of course, the RS4's appetite for asphalt remaining ferocious, insatiable and ceaseless. Its 265-section front tyres are 10mm wider than the old C63 rears! You point, it goes. Wherever, whenever. It just feels a little one dimensional at road commitment levels, even in these conditions. That the Mercedes offers such a rich experience, with speed comparable if not equal in these conditions, only compounds the Audi's issues. If it's not demonstrably quicker, then what's the aloofness for?
We tried two RS4s in our test, cars with and without the Dynamic Ride Control suspension. While the latter delivers some additional comfort at low speed, it does so at the expense of control, the car feeling vague and imprecise. The more aggressive modes restore some order with ride quality taking a hit, making it feel a rather awkward compromise. The standard set up, though firmer around town, does at least give a sense of purpose and connection to the RS4's suspension.
Even with a different set up, the RS4 can't win here. To describe it as ordinary would be unfair, but neither does it feel as special or exciting as you want from a car that's £77k as tested. There's pace and grip and ability to spare, but it achieves those by making the driver feel a little surplus to requirements. Of course that will appeal to as many as it puts off, the combination of maximum performance with minimal effort is as successful for Audi Sport as it is well practiced. That arguably wasn't the case with the previous RS4 and its 8,500rpm V8, so from a usability perspective the RS4 is improved. Trouble is the C63 has evolved too, from the slightly wild 6.2-litre car to a more well-rounded, more sensible, yet still hugely likeable package. You get out of it yearning for another go, a feeling that never materialises in the RS4.
For those after the fastest all-conditions estate there is, the RS4 remains the choice, and for all those people it will continue to impress, delivering on all the Audi virtues that have made the brand such a success story in the UK. If you're willing to sacrifice just a bit of that speed, however - and probably not as much as you think - it's the AMG C63 which delivers the more rewarding, more enjoyable and more immersive fast estate experience.
So is it the RS4 or the AMG C63 that takes your fancy? Let us know in the comments below; or for a range of great deals, checkout PH Classifieds and choose from hundreds of used cars on sale .
SPECIFICATIONS - AUDI RS4 AVANT
Engine: 2,894cc, biturbo V6
Transmission: 8-speed automatic, Quattro permanent all-wheel drive
Power (hp): 450@5,700-6,700rpm
Torque (lb ft): 443@1,900-5,000rpm
Top speed: 155mph (optional 174mph)
Weight: 1,790kg (including 75kg driver
MPG: 32.1 (NEDC combined, 19-inch wheels)
CO2: 199g/km (19-inch wheels)
Price: £59,740 (as tested £77,720 comprising £645 for Misano red paint, £900 for head-up display, £1,250 for driver assistance pack- tour, £1,000 for parking assistance pack advanced, £400 for red brake calipers, £525 for advanced key with boot opening, £2,000 for 20-inch five twin spoke edged design forged alloy wheels in silver, £200 for electrically adjustable front seats with memory function for the driver's side, £850 for RS Matrix LED headlights with LED rear lights and dynamic front and rear indicators, £175 for storage pack, £100 for extended LED interior lighting - multi-coloured, £1,200 for RS sport exhaust system, £2,000 for RS sport suspension plus with dynamic ride control, £1,250 for panoramic sunroof, £300 for heated front and outer rear seats, £125 for folding, auto-dimming and memory function door mirrors, £1,450 for top speed restriction increased to 174mph, £350 for full leather pack, £250 for tyre pressure monitoring display, £50 for smoking pack, £750 for Bang and Olufsen, £325 for Audi phone box with wireless charging, £630 for delivery charge, half a tank of fuel and number plates, £1,200 for road fund license and £55 for first registration fee)
SPECIFICATIONS - MERCEDES-AMG C63 S ESTATE
Engine: 3,892cc, V8 twin-turbocharged
Transmission: 7-speed automatic, rear-wheel drive
Power (hp): 510@5,500-6,250rpm
Torque (lb ft): 516@1,750-4,500rpm
Top speed: 155mph (electronically limited)
MPG: 33.6 (NEDC combined)
Price: £70,130 (as tested £82,735 comprising £1,695 for Driving assistance package including active blind spot assistance, active land keeping assist, BAS Plus with cross traffic assist, Distronic plus with steering assist and Stop and Go pilot, pre-safe brake with pedestrian detection and presafe plus, £2,595 for premium package including exclusive package, keyless-go comfort package, Burmester surround sound system, LED intelligent light system, panoramic electric glass sunroof, £700 for AMG interior carbon fibre trim package including analogue clock, centre console in carbon fibre optic, door panels in aluminium trim, £765 for AMG driver's package, £335 for 360-degree camera, £1,000 for AMG performance exhaust, £4,285 for AMG high performance ceramic composite braking system, £585 for AMG night package and £645 for brilliant blue metallic paint)