Steve,

I just finished reading thru this thread and I noticed no one has mentioned sealing the aileron hinge line. Have you done this?
Last summer I assembled a GP G202 ARF and it tip-stalled so badly when slowed for a landing that I was afraid to land it. I was letting a more experienced pilot land it for me and even he sometimes had trouble. I tried reflexing the ailerons without helping. I then sealed the aileron hinge-lines and Voila!! no more tip-stalling problem, gone completely. It is now a real ***** cat to land.

Just my experience....... Bob