I did this at LVMS in Vegas as well. You pay for how many laps you want to do, and an instructor sits in the car with you and comments most of the time while you drive.
You tell them ahead of time your experience level, and they'll tell you to go faster or slower depending on how you are doing.
Since I did three days at Ron Fellows' High Performance Driving school the day before this, I got to drive a 458 Italia in Race mode (
they don't put it in Race mode much), and haul on a V8 Vantage. I also drove a Gallardo Superleggera LP560, but I didn't fit in it properly so I couldn't get comfortable going fast.