I've got one I built and have been flying for the past 2 years at least. I've got an OS 46FX on it with a 12.25x3.75 APC prop and the power is great, very stable inverted. Can drag the rudder all day long without control problems, and with such a fast roll rate a flame out isn't a big deal with a snap of down elevator, roll it over and put it back down. Only problem I see with it is the tiny elevator, it's hard to get good control in a hover but if you stay on top of it it hovers great. I'm thinking about adding some counter balances on the rudder and elevators for more authority.

-Kelly