Got these to replace a knackered gaming headset that I never used the microphone for. Those cost about twice as much as I paid for these, and they're at least comparable in sound quality, possibly better.
Given that I am excessively sensitive to sound due to Asperger Syndrome, it was essential that these blocked out background noise well so that I was not unduly perturbed in noisy environments. They have helped me get through long workdays in an open-plan office and crowded Tube interchanges, probably better than my previous pair.
Obviously as I wear them for literally hours on end I can judge their comfort better than most - it's not perfect, sometimes I have to slip them off my ears for a few seconds, but they're certainly not painful and I'm still happily using them eight hours a day, five days a week, without any problems in durability.
The long cord is a bit fiddly as others have said but they come with a belt strap to wrap them around - although personally I actually find that more fiddly yet, so don't use it anymore. Your mileage may vary.
Ultimately, though, these headphones are worth substantially more than you're paying for them (I paid eighteen quid - they're twenty-five quid at the time of writing and I'd still call that cheap). How can you argue with that?