I bought a pair of Sony Noise Canceling headphones in advance of an airplane trip. They did a decent job of reducing the airplane noise Sound Quality They did a decent job of reducing external noise, basically by creating a low-level hum that made it much less noticeable. However, once the external noise source is gone, the hum remains. So, without any noise to cancel, these head phones do not osund as good as good headphones without the noise canceling feature. Comfort These headphones were decently comfortable. In use, I've had them on for up to 2 hours without a problem Design they do what they are supposed to do Durability They seem to be very well built. There have been no issues so far.