RC4 transponders (3 wire) should work. The decoder was updated last summer.

Yes, I think there will be 3 primary classes: Novice, Pro4, and 1:8 e-buggy. We can run other classes if enough show up on any given night of course, but I expect those 3 to be the only classes with a consistent turnout. Novice we'll let pretty much any vehicle run as long as the driver shows some level of control over it.