How about a Saito 72. I have one on my Morris Knife and love this little engine. Runs like a champ, and starts so easy. It's a prime and one back flip engine. I run mine on 15% and is has gobs of power. I think it would be a great engine on the H9 Ultra stick, and it won't ring your ears! hehe Nice and peaceful sounding engine. I like flying my Knife just before Dark...I go out and fly my big gassers for practice during the day, and then bring out the Knife in the late afternoon and evening and it's so nice and quiet and it's a fun plane too. I've also flown the Ultra stick and those are really fun also...I like doing crow landings with those...it's fun letting one of those just crawl in and throttling it to whatever spot you pick to land it. I think it would be a really fun plane with the Saito and the power would be a blast too. With the bigger prop it would make for even slower landings, and control authority would be increased.