One the best stock drivers in Sydney drives a FKO4, with rubbers tyres, X-rays are the most popular cars in Sydney, support & help.
there is alot of competitive TC4's out here as well both plastic & graphite shells <PS why not graphite? RC boys has it for $50 bucks compete graphite uprade> & alot of the parts from a TC3 are compatable with a TC4.
both very strong cars, Pro4 seems to need sorting, but if that is what you like you will try harder with ever one you like the most..
have you looked at a yokomo CGM (tub yoko)???
I drive a Tamiya Evo4 & love it, the car is dialed in for our track, I just need to fix up my driving..hehehe
good luck