I recieved a GP T-34B Mentor for Christmas. It calls for a 61 to 91 2-s, a 91 to 1.20 - 4-s. I was thinking of a Saito 100 but just can't get any enthusiasm for another 4-s. Would a Zenoah G23 work ???????????????? I have one G23 in a PICA 1/5th WACO and love it. I own a OS 91FS (4 stroke) and although it runs great and idles fine, don't like the banging sound when idling and intense vibration. Its in a Ultra Sport 60.