Everything is in the title. Huge listening quality (threatened This MJ I'd known for a while I found out a breath that marks the rhythm !!!) Isolation of total external noise (not music in openspace I almost do not hear colleagues !!!) Listed comfort I have never any discomfort in the ear (which is not really the case with other headphones) I run with sports side (they stay in place without any problems) and that for over 2 years without any deterioration The only problem is that I despair of finding equivalence in pedestrian kit (I'm still looking)