I get crazy stuttering with V-Sync on - dunno if that's something people have considered or not.
I seem to get it with it on and off unfortunately, so far I've read that the follow settings dumbed down to med/high should help: Shadows, Textures & SSAO. I'm going for a play with it just now anyway to see if I can find the route of the problem, I know it doesn't stutter with the 'high' preset.
A little part of me is wondering if its down to Vram usage, hitting over 2GB at 1080p...