I use these at work; I listen to them for hour after hour.  I'm very happy indeed with the comfort level;  They are open-back design but the amount of sound leakage isn't so much it annoys the neighbours.
 
I compared them to a colleagues Grados for a while; The Grado's defiantely sound different but is different the same as "better"?  I decided the grados might kjust have the edge but when I gave them back I was happy half an hour later or so.  and the Grados can be heard clearly by the neighbours on low volume levels.
 
Very happy with these; might upgrade one day as I know there is better sound out there; but I've been using them for a lot of hours now and I'm still a happy customer.

I've had these headphones for a few years now and I still love them.  They are noise canceling closed back headphones and that does make a difference to the sound.  I occasionally swap my usual open backed headphones for these and listen to something rocky and I'm amazed at the extra punch and the details they find that my usual phones don't.  Changing headphones / speakers nearly always brings something new out of the music.
 
I usually use them to listen on the train - mostly to pod-casts and occasionally to music; With the noise canceling switch on the air-con and general noise of the train drops away allowing me to listen without having to turn the volume up to much.  But the beat of mobile-phones keeping in touch with the base station quickly becomes annoying so I have to turn it off again.
 
With no noise canceling circuit the sound is still very good and the isolation from the foam bads is worth having on the train;  They are comfortable to wear but my ears get hot after an hour or so.  Also I find rock tracks become tiring after a couple of hours and go back my usual open-backs 'phones.
 
When I take them off on the journey they don't sit comfortably around my neck; so if I'm not wearing them its better to put them away in my bag.