I have done "World Class Driving" a couple of times. WCD used to offer half day supercar thrashing sessions on public back roads all over the country (AMAZING!!) But they sold out the company and now only do "spirited" drives through the desert near Las Vegas now (BOOR-ING!). I would not even bother with WCD now.
Didier Theys left WCD and started his own company with a partner and it is much like the original format. Not cheap but you do get to have a BLAST thrashing Lambos and Ferarris etc. Check out
www.DXLus.com
-Mark.