I have that motor and gearbox. I've had 6 flights on my ME, have stripped the Himax spur gear on 4 of them. Started buying spur's in bulk (2 to a package) but have now decided to just order the Cobri. The other issue is that I'm tending to beat up the airplane with deadsticks (it is a terrible glider) when the powerplant fails.

My experience: Avoid any situation where the prop is forced to stop under power. That means only hand launches unless you've got a paved runway. With the tiny wheels and wheelpants the aircraft will nose over quickly and under takeoff power this will strip the spur at minimum. Similarly, on landing the prop had better not be turning under power at flare, because the airplane will probably nose over and the same thing happens. I've also noticed that this spur stripping tendency gets worse the bigger the prop, and I simply can't use the 12x6, although I love the performance.

This is a bit OT, but I must say that although I love the remarkable power of the new brushless motors and today's generation of lipo's, I am astonished at how flimsy the rest of the drive train tends to be. We have tiny, tiny, set screws on the spur and on the pinion that are almost impossible to tighten sufficiently, fragile plastic spur gears, ridiculous prop collet lashups that provide insufficient purchase to a tiny shaft, etc., etc. Finally, my most recent brief WOT static test resulted in both blades of the flimsy GWS SF orange plastic prop separating at the hub and flying some 20 feet!

By the way, in case I haven't mentioned it, really love the mini-edge.

-- Mike