There were a lot of P Zero bodies at the US Indoor Champs. I think the popularity is due to the safe feeling. It has downforce in the rear but plenty of steering. There were a lot of Corvettes as well, and the Corvette is supposed to be good in high bite as it is a little less twitchy...but I have not tried it yet. None the less, the McAllister MX Stang (Mustang) was on the winner, PF Corvette on second, and I believe a P Zero 3rd.

....Just confirming that there are many bodies that are capable in USGT. Run what you like.