I have been using an XBOX branded wireless headset for a while. I honestly thought it was OK!
I recently purchased a Steelseries 7X and the difference is night and day!
I have a larger head, and after playing for a couple hours I would get weird headaches and couldn't really figure out if it was the game or what. Turns out it was the XBOX headset, it is super tight. I put on the Steelseries and it doesn't squish my head.
So what headsets are you all using on XBOX?