TechnoTonyI haven't had the chance to wear them for a long session yet, but first impression was that they are quite comfortable. I have a little bit of a rough time with the K7xx because they seem a bit loose and there isn't a way to really adjust to a specific "tightness" with the self-adjusting strap. The K553 doesn't give me this issue, and I really enjoyed the solid noise cancellation the earpads give me. I love open-back sound of K7xx, but for work I'll be using the K553. Earpads are firm but more soft/malleable than K7xx and seal well against my head. The build is very solid as well, doesn't feel as fragile as the K7xx