What we were looking for
Our winner clearly needs to exhibit exceptional poise and pace, but it must also be a pleasure to drive irrespective of the road, traffic and weather conditions.
List price £78,195
Target Price £78,195
The R8's performance is mightily compelling. Audi's first supercar is intense, mainly because it's crafted almost entirely from aluminium and powered by a high-revving 414bhp 4.2-litre V8 engine.
It sprints from rest to 62mph in just 4.6 seconds and doesn't stop accelerating until it hits 187mph.
Come to a corner and the R8 gets even better. Almost regardless of entry speed, it sticks to the road like week-old chewing gum before calling upon its quattro four-wheel drive traction to fire you down the next straight.
Body lean is tightly controlled, the sharp steering is precise and the brakes are hugely powerful.
It's safe to say that the R8 is great fun on challenging roads, then, but that alone would be insufficient to propel it to the top of this class. No, what really sets it apart is that it makes these stunning abilities so accessible and easy to live with.
The ride is fluid and extremely comfortable, particularly if you specify the optional magnetic ride suspension. The R8 is also perfectly happy to cruise around town, and its light controls are easy to use.
Refinement is another strength. Its slinky body scythes through the air with little resistance, keeping wind noise to a minimum, and the only sounds from the engine are the kind that you'll want to hear.
Inside, some of the fixtures and fittings are borrowed from other Audis, but it all looks great and the quality is as good as you'd expect from the company. The dashboard wraps around the driver, while supportive sports seats, a flat-bottomed steering wheel and an open-gated gearbox all add to the sporty feel.
And practical-ish, too
Finally, there's a surprising degree of practicality. You need to watch your head when climbing in and out, but there's plenty of leg-, head- and shoulder room. You can squeeze golf bags behind the seats and a suitcase under the bonnet. It's even easy to see out of.
To get your hands on another car possessed of the R8's all-round appeal - not to mention its ability to draw a crowd - you would have to spend well over £100,000. As a result, it's something of a bargain at just under £80,000.
Residuals should be very strong and the high running costs are par for the course given its performance. In fact, the only major downside is that the waiting list already stretches into 2009.
Porsche Cayman S
List price £44,250
Target Price £44,250
List price £129,002
Target Price £129,002