You just had to waste your money ang go with a OS huh. YS 63, use 14X4 (yea just as strong as the OS 90), YS 110 use 16 X 4. Just because the prop size will allow higher rpm, you don't have to use it unless its panic time. Learn throttle control, a major component to 3D, and above all, enjoy.

Stupidity has a price that is always paid.