My guitar (godin exit-22) came with 9's and medium/jumbo frets and I couldn't play it without pulling g,b,and e strings sharp. I couldn't even fret the strings down to the fretboard, I had to barely touch them, even after a setup and fret dress to cut the frets down a bit, and a new bone nut (the tech told me jumbo frets are popular with the kids today because of the shred/metal players that are popular that use them). I went to 10's, better, then to 11's which were much better. I guess I have a heavy touch. The tech told me that you can generally go 1-2 sizes up before you start getting fret buzz as the nut is generally cut to accomadate a size or 2 heavier strings. I just got a set of 12's and I hope these will prove to be even better for me. I have also noticed that the 11's tend to stay in tune longer, even when I haven't played for a few days, right out of the case.
Hope this helps, but it's just my experience.
Jack