Premiums for the Enzo are hand written off a manual chart...I don't think there are even standard underwriting formulas for the exotics...since unlike most cars, it appreciates in value. In addition, most insurance companies have caps (even through 1st party claims) for the amounts that are paid out for certain vehicles.
However for many non-rare exotics, insurance is actually quite cheap. I've seen some vipers, lotuses, lower end ferraris, porsches, etc, being insured cheaper than your run-of-the-mill Honda Civic driven by a 18 yo living in the city.
In answer to some of the claims related questions, State Farm will simply bill the drunk driver for any amount greater than his property damage limits. The enzo owner should have no out of pocket expenses.