I have used this headset for around a year now having received it as a birthday present. The quality is excellent and the unit is compatible with both my pc and my mac.
You do not need a sound card to use this headset as it uses its own which is housed inside the black box control unit. From here you control the volume, bass, surround mode (2.1 or 7.1) and also control the mic.
The mic is of average quality but is more than suitable for communicating over a game server such as team speak or even Skype.
There are only two speakers inside this unit, the surround is created using complex delays and reverberation from inside the earphones themselves however it is quite effective but not quite as effective as say a Logitech g35 headset which actually uses multiple speakers.
The earphone are fairly adjustable and are quite a comfortable fit however they do not feel as sturdy as one would like.
My only real flaw with this headset however is the volume, it is not exactly loud. More than suitable for games but sometimes you really feel like cranking the volume and this headset just doesnt allow you to do that.