It was great.  I used it for a little under 20 hours over the last few days, and it was comfortable the whole time.  I was also much less fatigued at the end of the flights, I think it made a big difference.
The set I used were the Avshop A450s, which cost about $250 and have an audio in and cell phone interface.  I think it's a rebranded lightspeed, and it was very comfortable.  avshop.com