I wanted to have a blue QuietComfort. I liked better than the silver. But then I need to know that all 3 bought headphones were not working. When first purchased on eBay, the noise reduction was virtually non-existent; the second, the battery door was broken. In addition, it constantly creaked in the right speaker. The third produced a loud whistling sound right.
I then researched the internet and found in an insightful YouTube clip, the differences between an original Bose headphones and a fake are shown in blue for the QuietComfort.
Now I have a silver Bose QuietComfort 15 and works perfectly as you would expect from Bose products.