I Pressed down with both hands on the 'wingplate' part of the XS. While wearing it of course.
If it (headband shapes down to your head) comes down a lot, the XS is being worn wrong. Best way to test if you have a good seal is to press on two wingplates / headband and see how much it goes down. Try to find the best fit instead of wearing them like over ears, where pads do most of the work.
Sound is MAJORLY improved, isolation is almost like the M100. Listening to music 10db more than the lifetime limit to the XS (32db) according to dosimeter.
Hope this helps you all. I'll elaborate on my method if need be.
Edited by Allucid - 4/9/14 at 8:36pm