I know I'm late to give my opinion, but the H9 Tribute would be a perfect canidate for your engine. I bought one last year so I'd have some place to stick a wornout OS 40la. That gives it great performance on low rates and phenominal performance on high rate. The UCD is also a great choice, I have one as well and LOVE it. I put the OS 55 on it and in the hands of a good pilot it really shines. I can only make glisten slightly, just need fewer work hours and more daylite time.