cappie, i have that combo in a slightly modified 4*. i added rudder, took out half the dihedral and clipped the wing. The 61fx will pull it through any standard maneuver and hold it on knife edge but a little more vertical power would be nice. If i repower i'll go with the 91fx or ys91 4s. The OS and Saito 4s would fly it great also. you'll have fun with it no matter what..........gare