there is nothing wrong with the spec tires (foam) for outdoors and indoors. Yes you do get more runs on a set as ya'll say. But I'll stay with my CRC foams for GT12 Down here where we run mostly outdoors. Like I said when they get wore down they are ready for the carpet. from my discussions with my tire tester on the asphalt the rubber tires made the cars chatter. So they would need something like the old days of capped tires.
Bottom line racing cost money so whatever you want to race costs -truing tires will always be here where it's foam or rubber. the same for balancing the tires (which I do). You race to have fun- at least I do .