It's great! Decent sound, pretty good noise cancelling. I often use it in airplane travel. The noise reduction effect leaves a very good impression on me so that I can rest quietly. I have been using it for a couple of weeks. It blocks out ambient noises no matter when you are on noisy subway or in crowds. So far so good, it is just what I need.
I would say these headphones do a good job of cancelling low frequency sounds (more bass like rumbling) than high frequency (treble) sounds. When I turn ANC on while right near my subwoofer for I feel as if the high frequency sounds are slightly reduced while the low frequency sounds are significantly reduced. It is very similar to just putting earplugs in, but these headphones are probably more comfortable since they have a small hole in the earphones for ear pressure equalization so your ears wont hurt with extended use.
So it definitely cancels out ambient noise. That said, it won't mute all sound around you, if that's what you're asking. I love my set because it makes it easier to concentrate on reading in an open office plan. Hope this helps.
Noise cancelling is pretty much non-existent. It only adds an annoying white noise. I can hear myself typing right now, as well as the guy on the other side of my cube clearing his throat. So, I would say it's not good.
The noise cancelation is pretty good. Use these working in a data center. You have to remember that these, just like any 28db hearing pro, will work to Reduce low end noise. They do not block out noise which is great, so I can still hear fine but the headache that is a hot aisle full of angry fanwalls is far more tolerable.
I found the noise canceling to be terrible, and returned the product for that reason. I have a neighbor with a constantly barking dog. I got these to wear while gardening to block out the barking dog. It didn't work. If you wear them and snap your fingers, you can hear it clearly. Didn't block out any noise for me. As far as ambient noise, like airplane noise, ANY headphone will block that kind of white noise out IMO.