If you're getting the astro mixamp, why not get A40's also?
the mixamp is nice if you want to connect to the pc, xbox, ps3 at the same time so you don't have to switch everything when you shift, and it separates incoming voice and sound so you can adjust them "individually" (with the small knob). the big knob is for volume
if you're not "hardcore" or "trendy" don't bother with the mixamp. my brother has one he's trying to sell me for $50 and i'm having a hard time justifying that much even as PC is the only "console" i really play on
Well, Sennheiser are more known to me as a top audio specialist, when Astro have only became known to me recently since searching for a new headset. I'm glad someone has replied though cause I know it's a bit specialist and so few people would actually have them.
I need to buy a new sound card though, but a high end one, any recommendations?