On a spur of the moment I got a pair of Sony MDR-NC40 Noise Cancellation headphones. Now that I have more time for a marketing decision, I'd appreciate a user's review of Bose's QuietComfort 2 versus Sony's MDR-NC500D. I was originally going to consider Bose's QuietComfort 3, but after reading some reviews on Amazon and CNet, I think the QC 2 would be a better potential buy. Out of these two (three) models, which one is the best in noise cancellation quality, audio quality, and comfort?
With my NC40s, I feel the pressure of the actual headphones themselves after about an hour of usage. I'm thinking that I would prefer headphones that are padded and go around the ear rather than on them, but I haven't used the around-ear type so I can't be sure. The NC40s offer much better sound than my iPod earbuds, but the sounds are still a bit flat. I think that the sound quality in these two (three) candidates would be better than the NC40s.
Not counting price, which one would be the best? Then, which one would give the best value for the money?

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