Alright well I bit the bullet and here’s my setup.
Sennheiser HD518
Labtev LVA 7330 boom mic
Astro Mixamp Pro.
Planning to ‘mod’ if you will, my Sennheisers by adding the boom mic. Like this: http://www.head-fi.org/t/446329/fragtalitys-audio-technica-ad700-boom-mic-mod
Using the Astro mixamp, I will connect the headset -> mixamp -> xbox/computer.
Which raises another question. I understand with mixamps, for true surround sound you have to feed them Dolby Digital Live audio, and onboard SPDIF doesn’t do that. What would be a good option to get this going? An external soundcard? PCIe?
Recommendations for a brand would be nice, I was looking at the Asus Xonar line