RE: rush evo engine?
Most of the time people buy picco, rossi, etc for the name because its all they hear about. An OS CV-R 12, 15, or 18 will do just fine. There is a company that makes roto starts but I couldnt tell you right off the top of my head.
I posted about the OS engines because they are a little more user friendly and they are also eaiser on your wallet.