ive got the arf at 5 lbs with a 46fx. Hover at 1/2 throttle and will do most 3d maneuver's. waterfalls, walls, harriers are a little ugly but hey. I had a prob holding it in a hover. Could only hold it for 10 sec. Well i got a OMP540 profile and could hover it the first flight no prob. I looked at the tail and thought the se tail was too small. So im rebuilding it. Im putting the profile tail on it witch is a little bigger. If you click on the www at the bottom of my post you can see the progress.
There is a guy at my field that has one with a os 61. It flys like a pattern ship but NO 3D.
I would defanitly recommend a light power plant. os 46 or 50, ervine 53, etc...etc...
Hope this helps