No worries. I own 2 of them. Flew 2 seasons with my GP 1/4 scale Giles-202 and the second is new in box waiting for me to finish building my CMP Extra. I have tried several props on the engine and I have had great results with the APC 17x6. I originally tried a APC 18x6W (wide blade) which several O.S. 160 users seem to like but spool up was too slow for me. Its a HEAVY prop. The 17x6 can pull my Giles out of a hover. I just bought a APC 17x8 to try as well. I just pulled mine off my Giles for a cleaning and after 2 seasons with no afterrun oil and just running the fuel out of the lines there was no corrosion inside. Occasionally while flying extended inverted it would lean a little so I just bought a perry pump and am about to tap the backplate for the pump. All in all a great engine and it will start on the first backflip. Make sure to prime it until its nice and wet first through and USE A LEATHER GLOVE FOR SAFETY! I got lucky the other day right after takeoff my plastic spinner shattered. Talk about vibration! I had to kill the engine and deadstick. Perfect landing though. I think the 35 degree weather may have not helped. Thank god it wasn't on the ground while starting / warming up. Wasn't wearing any eye protection.