Pros: Noise cancelling does exactly what I want. Sound quality is decent but not great (and, weirdly, seems to improve when noise cancelling is on; probably my imagination, though). Pretty comfortable, but could be better.

Cons: Sound quality is not fantastic, and they definitely could be more comfortable. Also, the folding joints are a little odd; while it's nice that the headphones compact well, the joints don't seem to play well together, particularly, so folding them up is awkward.

Overall Review: I had a pair of NC5's previously, that I loved and used extensively for years, which finally died on me. Also, for people with unrealistic expectations: ANC headphones almost never cancel out high-frequency noise. So if you want to cut out an annoying coworker's voice, you're better off with earplugs. But they're great for fan noise, decent for passing cars, and work WONDERS on airplane engines.

Pros: Good quality sound, fairly comfortable, no reception problems.

Cons: Wrote a review just a few minutes ago, then found reference to my problem. Apparently, the headphones have built-in automatic gain control, which adjusts the volume anytime it decides there's too much/too little signal. That completely ruins any music with interesting dynamics, and kills game/movie soundtracks too. I was willing to be more lenient when I thought they were defective, but learning that it's a "feature" just makes me angry (especially because it turns out I can't RMA them and get a working unit, if they're broken by design).

Pros: Solid drive, reads just fine.

Cons: Very noisy, much louder than the drive it's replacing. Really took me by surprise.