Need help with finding a decent Audio card.

Hey everyone, so, I am building a faorly high-end computer near the end of the year, and am looking for something thats been around, is known to be good, and supports 7.1/5.1 sound, I will be using headphones mostly, and on rare occasions some crappy speakers (Nothing I really care about the sound that hard with, mostly the headphones) And would like some audiophile opinions on sound cards. The rig I have created as a base, just to take a look at what I could build now and switch out and min/max price-for-power is here:

Case: http://www.newegg.com/Product/Prod [...] 6811146051
Processor:http://www.newegg.com/Product/Prod [...] 6819115202
Motherboard: http://www.newegg.com/Product/Prod [...] 6813131365
Ram: http://www.newegg.com/Product/Prod [...] 6820231272
Video Card: http://www.newegg.com/Product/Prod [...] -_-Product (Getting two of these)
Hard Drive1: http://www.newegg.com/Product/Prod [...] 6822136322
Hard Drive2: http://www.newegg.com/Product/Prod [...] 6822152185
Power Supply: http://www.newegg.com/Product/Prod [...] 6817139009
Headphones: http://www.medusa-usa.com/roccat-k [...] p-967.html

I am completely open to different headphones but I am willing to sacrifice some quality for comfort (And I need the bigger cans, thus why I picked the roccats) I know that they are 20hz-20,000Hz and I am okay with that because of the comfort and the amount of tinkering I can do with them.

One of my friends suggested the Tritton AX360 with an Omega Stryker audio card (Thats what he uses)
http://www.newegg.com/Product/Prod [...] er%20omega

Like I said, I am looking for a good price, well known, and will be compatable with my new build. I will be using this computer for lots of gaming and listening to music frequently. Thank you for your time.

I have read some reviews on the Tritton AX Pro's that say they pinch the ears somewhat and are a bit uncomfortable after time. I have already gone ahead and ordered my headphones so really all I need is the sound card, You say that this Xonar is a good card? And with a $25 MIRB its cheaper and better than the omega stryker? Really, my budget is probably $150 or so on the audio card. Unless it is a serious step up for another $35 or so.