So I've had the Sennheiser HD 518 headphones for the past few years, and I really like them. I wear them while I'm working. However, I'm changing offices to a noisier environment, so I wanted to get something that does noise cancellation, as the 518s make no attempt at isolation whatsoever. I thought the natural progression would be the Sennheiser PXC 450s, but I hated them - they felt cheap, the noise cancellation wasn't very good, and the sound quality wasn't anywhere near as good as the 518s. Back to the store they went. I'm currently testing out the AKG K 495 NCs and the Bose QuietComfort 15s, and I'm torn as to which one I like better. Does anyone have either and have any opinions? The AKGs definitely have better sound quality, seem better built, and have the advantage of a built in rechargeable battery / still works with the noise cancellation turned off. However, the Bose have better noise cancellation and are more comfortable. If it weren't for the comfort thing, I'd say sound quality trumps the noise cancellation and go for the AKGs, but that does concern me - if I'm going to be wearing them 20-30 hours a week they have to be comfortable. The on-ear design seems to hurt my ears after an hour or two. Does anyone with the AKGs have any experience with that? Do you get used to it or is it just a constant issue? Thanks!