Normally I would recommend prop saver for beginner, but the largest prop saver I have found only fits 1/8“ shaft, commonly found in the old style FT power pack, but not for the new C pack. I personally don’t think you need 10” prop on Simple Cub. The best props for 9” and down are the GWS HD or slow fly prop, super light, flexible, cheap, produce more thrust and draw less amp. Also, I would avoid APC sport on electric motor. Sport is designed for gas engine with much more mass around the hub than APC E or slow fly to handle the torque and vibration from gas engine. The downside is that electric motor might spin at a higher rate than a gas engine, and the acceleration is much faster, the mass/wight of a sport prop will put extra load on the drive shaft and eventually cause premature failure on bearings. Also the sport prop produces less thrust than the E prop.