I have 3*Leo 37 and 2*Leo 60, all of them run perfectly.

I run the 37s on a fun fly using a Genesis throttle pipe, the engines all have instant transition throttling up and down constantly as I try to hover, and I am using no nitro or 5% nitro if I am feeling rich.

I have used the same 37 with Genesis pipe in my English Electric Lightning weighing 5.5lbs and it screams around the sky.

They are powerful but I don't know how their power to weight ratio compares to others. The 60 is a bit on the heavy side. However as you can see from the number of Leos I have bought I have no hesitation in buying and using them. Who cares how long they last - they are so cheap! What matters most when doing low level fun-flying is an engine that keeps running and responds instantly and all my Leos have not even hiccuped once.

Harry