This card is 25-30 usd only which is very inexpensive, and it is a noticeable improvement over my realtek 892 onboard sound, I only have some cheap Plantronics Gamecom 367, which sounded boring with the onboard sound, but after setting up the card they sounded more transparent and alive (for a 30usd headset). This card will work nicely with ANY gaming headSET and some EQ tweaking, I've tested it with siberia v2's and they sound better than the usb soundcard, a razer carcharias sounded better too.
The only major problem with this card are the drivers, this card is NOT easy to setup, if you buy this card it is normal if you don't notice any improvement at first, but you need to know how to set it up correctly, first of all throw away that garbage driver cd, and download the latest updated drivers form here:
http://maxedtech.com/asus-xonar-unified-drivers/ ASUS site drivers are garbage too.
This drivers will work for any asus xonar card and some auzentech too, try installing the cmedia panel version without gx enabled, you shouldn't use gx (or xear 3d) because it is just a buggy feature, it made some of my games crash, then you need to set your windows sound output to 24bit/44100hz and then disable all the features on the card. You can use the headphone amplification and EQ features since they improve your experience, try to control the volume from windows and move the headset cable volume control to maximum, that improves SQ and finally NEVER use or connect front panel audio, front panel connections on pc cases are normally very bad quality, use extensions and connect your headset directly on your card.
You can try different configurations and see whats best for your headset and audio needs, for example, if you like dolby headphone use it, I personally never use it because it just ruins music and in games removes the sense of distance since it normalizes the volume, and that's not good for cs global offensive.
This card will work nicely with ANY decent gaming headset,the best headset I have used is the corsair vengeance 1300, but you can use creative tactic 3d sigma, razer carcharias, razer kraken, steelseries siberia v2, steelseries 5h, logitech g230, but those are gaming headsets, if you want high sound quality try beyerdynamic dtx 910, sennheiser hd 4x9, akg k240 studio or audiotechnica ad500x with the zalman clip on mic, that will get you the best results.