I've got a Ripmax Zephyr which I flew for a while. This is a 3 channel floater. I managed to make it do loops, but once the wind caught it a quarter of the way around and flipped it over. I heard a loud crack. When I landed the plane I could see that the spar had broken. An easy repair as I was lucky that the wing didn't totally give way. Others with this plane have not been so lucky. I 've heard that rolls can be done with 3 channels but you lose a lot of altitude....