Ummmm, by RS4, do u mean mtx-2, and mtx-3? cause if thats what u ment then uhh, i didnt have to spend much money at all. those cars are PRO cars..........hopefully hpi's new car can take a hint from one of them so then maybe people like u wont have to suffer with their rs4.....oh wait, maybe uve graduated to the rs4 2........Wow!!!! Turnbuckles