I know someone who tracks their Cayman (just recently traded it for a C6 Z06) and he uses Hagerty for it. I discussed the track insurance with him. He mentioned that State Farm's insurance policy does'nt mention anything about wether it covers on the track or not. I've heard of someone getting their total loss on track handled via state farm and they didn't deny the claim. It's a safe bet that these two companies are the only two you should trust.
A far as taking the daily to the track, IMO, use the opportunity to learn the skill and limits (both yours and the vehicle, but most importantly yours) and don't try to attempt to break records or drive too aggressively. This is your daily and your primary source of getting to and from a to z.