These are the best and comfiest headphones I have ever worn and had the pleasure of hearing through, the sound is so crisp and clear and the volume goes very loud so you don't have to pump it up in the volume controls on your PC.
The microphone is extremely clear and the noise cancelling is the best i've ever heard. No PC or other background noise at all is transmitted, not even a big fan pointed straight at my head.
Usually on headphones I get agonising pain in my right ear after prolonged use but these are so comfortable and they block out a lot of the background noise so you don't have them louder than you're comfortable with, you could pretty much wear these forever without ill effects.
Well worth the money for the amount of satisfaction you'll get out of them.