I faced a similar mounting dilema but ended up getting them center mounted. They do great in the trees and pow as well as on rails and big jumps. At the center mount they are the best most complete skis Ive ever had.
mine are at 1 back, but I think I have to remount them and I'm just going to put them at center. The only reason I'm questioning it is the fact that the sidewall part is not even close to being in the center.