Anyone familiar with "Drive your dream" exotic rentals?

I'm thinking about doing an exotic group rental with "Drive your dream". One day rental in a group with several cars, F430, Aston Martin, Porsche turbo, ZO6 and a Gallardo. You switch cars every 30 minutes or so. I'm a little hesitant over liability issues. It looks like the renters are responsible for all damage through their own insurance (makes sense) but also responsible for mechanical damage unless it's clearly a warranty repair. I think you're even liable for loss of revenue during the time a car is down for repairs. I'm pretty sure my Allstate coverage won't deal with that.

Anybody used "Drive your dream"?