I'm thinking of building a 400 or 500 now and doing that. Speaking I've managed to send both the mSR and CPPro2 sailing at full uncontrolled throttle in my apt, I've found they aren't near dangerous enough. Hhahaha. Now I just need to decide on what and the budget associated. I definately want something stable and with an aluminum head. Now more plastic parts. Just easily broken cheap blades to save the head unit. I've learned I'd prefer to have the blades be the "fuse" rather than rebuild the head. Just stock up on blades and flybars.