I've been using decent headphones for a while now, I've had various headphones, including Beyer DT880s for a decent period and more recently (month or two) picked up some hilariously large DT150s in an attempt to resolve the comfort issues I have with my ridiculously large ears.
The main issue I've had is pressure on my ears from the driver (pads are too shallow), or rubbing against my ears (hole is too small). With this in mind when I was looking for some cheap headphones to use at work, I decided to grab some Koss Portapro as they're a completely different design to those that have been irritating me, and not too expensive.
It was a good selection - they are some of the most comfortable headphones I've ever worn, and having gone bald, I don't even get annoyed with the headband trapping hair.
And, I am ashamed to say that I can't determine a tremendous difference in sound quality between when I am listening at work and when I am listening to my superior headphones at home. They are perhaps a little more refined, but the difference in absolute quality (as opposed to different sound) is not tremendous, and they irritate my ears.
It would seem the prudent decision at this point would be to stop throwing money at manufacturers that can't even make a comfortable pair of headphones, and just get Portapro. If only I had discovered these earlier!