headphone amp - project headbox mk2?

[bledd]

currently I have..

xfi xtreme music / xonar dx (i can test both to see which i prefer)
HD 595

thinking of getting a headphone amp, for playing games and music.

how do these compare?
http://www.project-audio.com/inhalt/en/pdf/headbox.pdf



or would you say, sell the current cards and get a Xonar STX?

 

[bledd]

would you go back to just using the soundcard?

 

[bledd]

hmm, mixed responses

i won't be making my own anyway, and don't want to spend over £100