I once had a Dave Patrick Ultimate with an OS 108 in it and it did just fine. Run a Slimline pitts muffler. I would however suggest not adding ANY extra weight. I don't remember what mine weighed but Ido remember that anything more and the 108 just wouldn't cut it. I ran a 2 servo setup for the ailerons and linked the upper and lower ailerons with a pushrod. Worked just fine and eliminated 6 oz. Use an APC 15X8 prop.