Like you, I've had the Sony for years, and agree they become uncomfortable after a couple of hours.
In the front cabins, AA passes out the Bose QC2; these are great for comfort (sound cancelling ability is about the same for both), and I can wear them for 10 hours without any problem. Strictly in terms of comfort, I'd go for the Bose. They do not nest as compactly as my old Sony set, however. I always carry the Sony but use the airline's Bose.

This subject is probably handled in great depth in the technology forum.