Are you a poser or a purist? Be honest. Provided you don't crash into a parked car while clocking yourself in a shop window, there's nothing wrong with buying a sports car to flatter your ego. But if you're more concerned about perception than performance, the RUF 3400S is not for you. It's a Porsche Boxster. Yes, RUF have modified this particular version to blast from zero to sixty in well under six seconds and out-corner a Ferrari, but it's still a hairdresser's car. Compared to the fearsome 911, the Boxster has about as much street cred as a dark blue M&S suit.

Ah, but if you are a purist, get ready for a treat. You'll already know the Boxster has one-up on its 911 stable mate: a mid-engine layout. (For the blissfully ignorant, the 911's engine sits behind the rear wheels. During heavy cornering, the car must use clever tricks to stop the rear end from saying, 'Wait a minute. Wait a minute. I'm the leader.') What purists can't know- at least until they drive the 3400S- is the Boxster's true magnificence. The official Porsche product just doesn't have enough power to exploit the Boxster's dynamic capabilities. In other words, it's too damn slow.

The Jaguar XK8 is a classic. Six years after its debut, the design is still fresh, bold and dramatic. It's one of those cars that somehow looks fast standing still. Okay, viewed from the side, the boot is about two feet too long- thanks to US regulations requiring all expensive cars to accommodate two golf bags. Even so, the Jag rules. Freshened Porsches, Mercs, Beemers and Lexi still can't compete with the XK's svelte aggression. Slinking into the club's parking lot, the Jag proclaims, 'Look out boys, this cat has claws!'

Except it doesn't. Yes, the XK is fast. The standard 4.0 litre car zooms from zero to sixty in 6.6 seconds. The supercharged XKR makes the same dash in 5.1. But anyone who loves life (or hates insurance forms) shouldn't try to carry that speed into a corner. The heavyweight XK8 is a cleverly disguised boulevard cruiser. Ask it to change directions quickly and, well, hippo-type wallowing ensues. It doesn't matter if you try to counter the XK's 'hard-a-starboard' body roll with brakes, acceleration, opposite lock or prayer. Bad things happen. Owners quickly learn to restrict their fun to straight-line blasts or slow motion posing.