Roger on the differences between same size props. My Fuji BT-50SA

1) Top Flight (wood, square ended blade) 20x10 ==> ~6200rpm

2) Mejzlik (carbon fiber) 20x10 ==> ~7000rpm

3) Bolly (carbon fiber) 20x10 ==> ~7800rpm

NOTE: I was running the Top Flight during my initial break-ins and have not tried it since changing from 25:1 oil ratio to 40:1 oil ratio. Also more refined adjustments have been made since. I'm still shy of 2 gallons total run time and I'm still getting oily black residue from exhaust, so the engine is still very much in a break-in mode.