I run at a track in Bloomington IL and we run a gearbox class every week. They race trucks on carpet with foams. Very strange but I have never heard any complaints. We use to run jumps and bumps but dont now that we built a new race facility with new carpet. We have a ride height restriction of 1/2" and a minimum tire size of I think 2.5" (so guys dont run touring car tires). They run trc blue and green compound foams. The trucks are fun to watch and look to handle well, I know I hate to marshall them things though.