I did a GP Skybolt for a guy a few years back, powered by an OS 1.20 Surpass. The heavy engine required weight in the tail to balance, even with the radio equipment at the rear of the wing opening. Power was more than adequate with what seemed like unlimited vertical doing rolls. This was before the days of 3D, so I can't comment on hovering.
Full throttle flight speeds were very fast and you should heed the instruction book warning about doing very stiff, slop free control hookups. If you're not accustomed to throttle management, this would be a good time to learn it!
Another guy in our club has one powered by a .91 Surpass, somewhat overweight, and it flies fine.