Pros Light, comfortable, good sound, single cord with volume control, lifetime warranty
Cons None that I've found
Summary As I'm not an audio expert, I can only state a subjective, personal opinion. I only purchased them to use around the house to use with my small MP3 player. The earbuds that came with the player I use primarily for portability when on the run for various errands. I find the QZPro comfortable to wear and are light weight. The sound is good and the noise cancelling is adaquate especially since I didn't actively go seeking that feature figuring I'd have to spend a couple to three hundred dollars to buy quality noise cancelling.
I considered the Koss PortaPro and the reviews were great but one comment caught my eye so I went to the store and tried a set on. It was true, the PortPro had a tendency to pull your hair out by the roots when removing them. Could be I just didn't have the knack but it was enough to make me start looking for an alternative.
Anyway, after using an on-line coupon and free shipping at Buy.com, I paid $35.00 for the set. At that price, I couldn't go wrong and so far, I've not been disappointed.
Pros Size of the earcups
Cons Cord length
Summary Good buy, I'm not sure about the durability.
Pros Very good sound and noise canceling
Cons None for me
Summary I am not really an audiophile, but I do like good sound from headphones. I bought these for use on planes, and they do a very good job. The noise-canceling is very effective and allows listening to music where it would otherwise be almost impossible. I travel several times a year on business but not enough to justify a pair of the Bose QC phones. For the price these Koss phones meet my needs quite well.