I have one of their props it's a 54x24 GSC tech prop. I did my first flight of my Hummel UltraCruiser with it. 37hp dual ignition Scott Casler half vw. It ran about 42 kts in level cruise at full throttle. Climbed about 300fpm. Wasn't that great. I saw better numbers (Not by much) with my new Prince P-tip 54x22. The Prince prop is thinner, lighter, and just "feels" better. Less vibration, quicker off the line as well.