Thanks for the prompt reply....So the G90 is definately more powerful. I guess I'll be getting that one. As for the prop size... I've seen a lot of guys using 14x6s or even larger props on this engine ...isn't this really bad for the engine...overloading? Personally I was thinking 13x6 for sport/aerobatics and 14x4 for 3D...what do you think? and oh yeah will it be as happy running a 12x6?