OS RG is all I will run. Two hundred bucks cheaper than the "top tier" engines. I don't care what power those engines promise. I could use that extra money to buy a two speed for my 9.5 and a JP-2 (the latter of which I did) at which point, no engine could keep up. But I am cheap, so thats just me. I suppose if I raced, I might drop the three plus bills for a better engine, but for now my RG does plenty good waxing my buddie's Hyper and my other buddy's Sportwerks .26 (the driver of the sportwerks kinda sucks though, otherwise I think that motor would have the edge).