I'm looking for a nice set of cans.

Yep Audiogon is one of the few places on the internet where that is not a dirty remark.
My current set of headphones broke in half the other night. So I�ve decided to step up my head phone game and buy a really good pair of head phones. Something I can use on my main system but also when I�m traveling.
After some quick research I realize that I am very behind and out of my element with headphones. I don�t know the pros and cons of open back vs closed. Which brands are currently the best? I�ve looked at Sennheiser, B&W, and Grado but I�m open to any brand as long as the quality is there.
My uses are primarily for travel. In the car, train or plain I�d like something that can block out ambient noise and not annoy the people next to me with music leakage. If I had to prioritize my needs it would be, 1: Sound Quality. 2: noise canceling 3: staying at or below $300.
Thank you for your help and thoughts.