I use a 9cap with my goldberg bipe. I only just started playing with it last fall with two servos and slaved the upper alerons with a mechanical linkage. I wanted flaperons to slow up the landing speed a bit. It works well but it appears to have so much aleron surface that if you hit the flaps the plane turns toward the ground. Oppisite if you hit the spoileron. I need to compensate with more elevator and i think it will be ok. Just surprised me, the big stick always got a little up lift when i hit the flaps instead of nosing over.