i7 4770k OC'd to 4.5
Sapphire 7970 3GB
8GB RAM
The stuttering still happens during cutscenes...at least if you have 60fps enabled. I'm disappointed by that.
I'm getting a definite boost in performance using Mantle, even compared to Mantle before the patch. In Redcliffe there were parts where I was in the 30'swhen using DX11 and now I'm in the high 40's low 50's in the same parts.
There is also performance gains using DX11 as well compared to pre-patch but Mantle definitely gets me higher FPS'. If you enable triple buffering via user.cfg file while using Mantle, most of the hitching I was encountering during framerate drops went away for the most part (I had a bad hitching problem when using Mantle before I did this).
Now I just have to make the choice of whether or not I want to give up the ability to take screenshots in order to get better performance. It's a harder choice than you might think.