In our world of eagle-eyed policemen and wanton thuggery, the idea of a Q car has a lot of appeal. However much we like the idea of showing off, discreet speed is often better than waving your knickers in the air, and if your car looks unexciting then fewer people will want to vandalise or steal it. The premise is: have more than you show, speak less than you know.
Now I know we peddle out the old clichés when it comes to buying used cars from our classifieds - and we've all read hundreds of times about that wonderful old Maserati or Lotus you can buy for the price of a new Qashqai - but just occasionally you find a car that seems to offer so much bang for the buck that it does make you stop and wonder, especially if it offers that discreet speed we're after.
I mean this immaculate RS4 B7 is up for £16,495 which, if spent on a new car, would buy you next to no performance in the real world, other than an Up GTI perhaps, and yet this humdinger of a four-door saloon will get you from 0 to 62mph in 4.8 seconds and sprint with eager ferocity up to its limited top speed of 155mph. This one's not too old and not too knackered, and it hasn't been stolen, as far as I can tell, all of which makes it great value. True, its enormous and attractive alloys do hint at its performance potential, and those sills and skirts don't help its Q-car capabilities, but to the casual observer it's still a boring old A4 in style and substance, and you could always debadge it for maximum under-the-radar motoring.
Under the bonnet is that luscious 420hp naturally aspirated 4.2-litre V8, good for 8,250rpm. There's a six-speed manual gearbox, with a usefully positive action and well-chosen ratios, and Quattro-drive to all four wheels. That performance is not only easily accessible it's also truly phenomenal, with instant power available at almost any point in the car's speed envelope. The boundless grip and superb handling are equally impressive as well - the four-wheel drive system pushed 60 per cent of the power to the rear wheels, unless it was needed more urgently elsewhere.
You really do ride a wave of responsiveness, power and aural pleasure piloting an RS4. It's an agile, subtle and delightfully well-balanced driver's car, and if you can afford to fuel it and insure it - both of which will admittedly cost you a lot - you'll have tremendous fun with it. All without drawing too much unwanted attention.
SPECIFICATION - AUDI RS4
Engine: 4,163cc V8,
Transmission: Six-speed manual, four-wheel drive
Power (hp): 420@7,800rpm
Torque (lb ft): 317 @5,500rpm
First registered: 2006
Recorded mileage: 72,000
Price new: £50,730
Yours for: £16,495
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