I too have the GP Ultimate with OS 70. I only have 2 flights on it but from what I have seen I doubt it will hover well. Just too heavy of a plane. My Cap with the same engine will hover at around 3/4 stick. The Ultimate tailslides at the same setting. It is a great flying plane but lacks the size/power needed for good 3D. Almost lost it on the second flight when I tried hovering because it took so long to recover. I ended up exiting inverted with full throttle to get out of the stalled situation.

Good Luck, Phil (Mesa, AZ)