Pros: Amazing active (NC off) sound quality. Full range response.
Cons: Not that comfortable for long periods. Active NC has weird distortion sometimes. Poor Internal build.
Warning: See Update (2014-12-15) below.
First, a disclaimer. My Head is of an above average size. 7 3/4 (XXL)
These headphones are very well made. In the world of plastic, it's nice to see headphones put together with metal and screws, though plastic is still heavily used. Because of this, they are heavy and ridged. The problem with this, is if you have a large head then they clamp uncomfortably to your head. Because of the stylized ear cups, you will find pressure on parts of your years. This is in contrast with most high end Sony or Sennheiser.
With a good headphone amp the fully off state produces good sound with good passive noise isolation.
With the middle "active" setting, you get a nice quality build in headphone amp which improved bass response considerably and is very enjoyable.
The full Noise Cancelling mode is inconsistent. It seems, based on the quality of your input, their can be a bit of a feedback loop where noise is introduced to the noise cancelling feedback.
Compared to headphones like the Bose, Sony or Audio Technica, this is a dirtier implementation.
The travel case, detachable cables and other accessories round out a very well thought out package.
Ultimately I regret my purchase, not because of the NC feature, value or any of these things, but simply due to them lacking the all day comfort I need for hours of coding at my job. Again, please take into consideration the size of your head vs. mine when reading this review.
These headphones were purchased used.
Update (2014-03-05): I still have these headphones. I'm not sure if this is intentional, but the headphones come with a second set of pads. I found these to be stiffer. This allowed the headphones to sit properly on my head and are more comfortable. Again, not as comfortable as Senns for example, but comfortable enough that the amazing sound quality is worth it.
Lastly, I can't seem to add a photo. I apparently lack permission.
Update (2014-12-03): Still using these headphones. So I apparently do not regret buying them. I can't find a pair of NC headphones that comes close to the overall quality and sound of these. One feature of note, is that they act as a headset for making phone calls. This is something I do regularly at work through our internal VOIP system. I also use the feature on my phone.