The only thing I did to strengthen my avistar was to add some triangle stock under the hoizontal stabilizer, I'm not sure it was nescessary, but I was a newbie and a guy at my field suggested it. Personally, I think anyone who has had trouble with their wing folding either had a defective wing, or was just doing something ridiculous like going full throttle down and pulling out hard. I have done the ultimate wing-test maneuver; a blender, and the wing has held up fine. As long as you pull back on the throttle when exiting a loop, you can pull out pretty hard without hurting anything.