I just ordered a saito .91 for my ucd to replace the old worn out os .70. should be here in a couple of days. i can't wait to get it out with the new engine. any suggestions on prop sizes? i was using an apc 13x4W. on a lighter note i haven't had any problems with the landing gear. with my os .70 my landings were dead stick 4 out of 5 times and had no problems with the gear. mine seems to float back to the ground like a feather.