I think that any USB device will be a bad idea. It eats CPU.
Not 100% sure, maybe some one can confirm this?
I use the zalman 5.1 surround head set.
The mic is a bit odd, but mic sound quality is ok.
In a GV you can hear if the bad guy is in front or behind you

That is nice with 5.1.
In theory you can also hear this in AC, but then again the bad guy is allways on my 6 anyway.