I've been using Tritton AX360 since they hit the market (2005? Early 2006? don't recall when).
I like them. Sure there are limitations but I personally like their 8 speaker set up. To the person who said hearing dialogue is tough on movies, I've watched SD-DVD's, HD-DVD's, and Blu-ray with them for sound and dialogue hasn't been a problem. Of course in-line controls have to be tweaked for different inputs, but that is expected.
As far as game play where location of sound is important (Say Halo 2/3), I found this to work well. No complaints, including size as these fit comfortably. I also haven't had trouble with the mic, but it is cheaply made.
What stinks about the product is the lack of DTS decoding. It is disappointing when you have a blu ray risk with Uncomped PCM and DTS-MA tracks, and you have to use the DD 5.1 + track, but the receiver only decodes it as regular dd 5.1. Considering this is for XBOX/XBOX 360 primarily, it makes total sense.
I recently contacted the company to order another set of headphones (the receiver can support up to two at one time but currently the company has not starting selling spare headsets in stores), which they will sell to me directly for $60/each.