I'm an oddity.
I'm running this on a Bootcamp partition on an Early 2008 Mac Pro.
I'd been running XP Pro for a long time. Some time after Jun 2010 I lost the ability to crank the graphics all the way up. I was bummed, but I stuck in there.
With NA requiring dx10 and Win 7 I took the plunge.
Out with the 250gb partition on a 1tb drive.
In with a spare 250gb drive.
Bootcamp installed Win 7 ultimate 64 smoothly.
Next I downloaded and installed SF2, Vietnam, Europe, Israel, Exp 1, Exp 2 and the DLC's. All of these are at the April 2012 patch level.
I am impressed with the improvement in performance! To think I was dragging my feet over this.
I am pretty happy with the game now even sans North Atlantic. I'll be adding the F-104's and fixing the ships before too long. I've paid for NA, but something broke in the purchase and I didn't get the link yet. I think I will wait on installing it until everyone here says the coast is clear.