Wow... won't hover with the .91 Surpass, eh? The only UCD I've actually seen in person uses this engine and seems to hover fine but I don't know how easily it pulls out. I've not flown it or seen what throttle level it takes to do it but have seen it happen at our field. Which prop are you using and what rpms are you getting? Maybe someone else here can offer a comparison with their same set up.

-s