I have a pair of the new Sony 7.1 Surround Sound Headsets and I can say they are pretty damn good. I've never tried Turtle but they definitely do a great job playing BF3, MW3, NBA 2K, etc. Like all the reviews say, the bass is kind of lacking, but it's hardly that noticeable in my opinion. And also, music on the PC sounds great too.
I just wish the Virtual Surround Sound was for movies and stuff too both on PS3 and PC.