I've owned quite a few engines, and the O.S. .15 FP is my all time favorite. Not a powerhouse; but quiet, reliable, and fuel efficient. I've got mine on a 99 in. Dynaflite Butterfly, that I use for training. The plane weighs around 3 lbs., and will ROG off our rough, grass field with an 8-4 prop. I usually get 10-12 minute flights with 2 oz. of fuel. I've had the engine on four (4) planes, and it's never quit on me.

Robb