My Evolution 100 on a Funtana 90 started right out of the box, idled and transitioned perfectly. Needed to lean the top end slightly, went flying. No problems, hovered the Funtana at 1/2 throttle with, shot skyward with ease. I am impressed with the engine.

LHS sells a lot of them, all have been trouble free. I agree with Dennis, it probably isn't the engines fault. However an occasional crapper can be had with any manufacturer, including OS.