I installed it and it the sound quality is great.
However, when I want to switch between speakers and headphones (say when my house mates are sleeping) i need to stand up and change the cords at the back.
Creative Sound Blaster Z SBX is an example of a card that can do this but I'm not sure how good that card is and I'd love to be able to do this for free with my Xonar DGS.