I went on a track day experience at Rockingham, organised by one of the divers at work. Now personally I didn't enjoy it when driving myself around. However going out on the track with one of the professionals at the wheel was tremendous fun.
I think what slightly tainted it for me. Was at the end of the day when we were all done and dusted, the diver, Steve. Introduced us to his latest acquisition, a brand spanking new Porsche 911 turbo. Turns out he paid all that money for the track day, just so we could sample the kind of car he'll be driving everyday. I always thought he was a tw*t before then, but that confirmed to me he was.