I'm running SMC 4600 and I think the others were also running SMC or Protek 6100. We were all running Tekin RSX's. We recommend full size servos only due to the tire size.

If a track were to do a "spec" class, I could see maybe a 10.5 or 8.5 motor, but honestly I think it should just be an open class. It's way more fun to drive these truggies hard like the 8th scale ones. And since it's open wheel, you shouldn't see the same aggressive driving habits that SC can foster.