I recomend a 46 through an 53 for the sig. I have one with a46 on it and it flies great. The plug in wings are great the only thing I did different is to use a spring instead of the 64 rubber band. I test flew it last week and man you can't count the rolls it can do, and it will jump off of the ground. Also watch the elevator rates if you are not use to a very quick plane,fly it on low rates first.