I tried them as an experiment on an old 1/4 scale Corby Starlet on the ailerons. Didn't change anything but put tabs on. 10% of aileron area. Had small size horn on the tab. As I moved in on the horn, one hole at a time. on the third hole in, it was as though you put the next size bigger servo in and increased the roll rate by 1/3. So they do work and not that big a deal to retrofit.