This is a great present; I got it in August last year when I turned 30. My choices were: Ferrari 360 Modena, Lamborghini Murcielago, Lamborghini Gallardo, Aston Martin DB9, Aston Martin V12 Vantage, Audi R8, Aerial Atom, Subaru Impreza WRC, Mitsubishi Lancer Evolution.
I went for the Ferrari 360 and the Lamborghini Murcielago.
If you have broad feet, don't go in the 360 unless you relish the thought of a high-speed impact, and subsequent vegetative coma, and death - I have broad feet, UK size 12 / US size 13 - and my right foot kept getting stuck on the accelerator pedal (which is pencil-thin), caught under the brake pedal (which is really wide). I have to say that it was an awful lot of fun though; the car is like an axe-murderer - may not be heavily-built, but keeps trying to kill you. It accelerates like nothing else I've ever driven or been a passenger in.
The Lamborghini Murcielago is a massive beast of a car, powerful but heavy. The manual gearbox I used was a bit clunky, and I found it difficult to select gears because of the "gate"-like design of the gearshift - in the 406, you basically pull the gear stick back to go from 1st to 2nd, push it forward to go to 3rd, back to go to 4th, forward to go to 5th. In the Lambo, you actually have to pull the stick to the side slightly as you push it forward, otherwise the gear lever just clunks against the metal guide. It's a very satisfying car to drive, and the noise from that massive V12 engine is just phenomenal.
I'm told the Audi R8 is a better car all-round than the Lambo, but I've always craved Lambo from when I was in primary school.
If I were to go do the supercar driving day again, it'd be the Aston Martin DB9 or DBS, and the Lamborghini Gallardo (lighter than the Murcielago, but supposedly just about as powerful, and certainly easier to drive).
Have fun, and don't scratch their fancy exotic cars! Here are two photos from my track day:
