I have the HD 600 and it's probably not going to be your cup of tea. Also decide whether you need an open or closed headphone. Open cans like the Senn means everyone can hear what you're listening to and so they are terrible as a traveling headphone.

All that said the HD 600 is a wonderful headphone but you can get pretty much the exact same sound from the HD 580 which is a lot cheaper. The Sens also need a headphone amp which can be a drawback.

The AKG 26p that I also have is quite excellent as a traveling headphone and runs about $40. I was fortunate to compare about 25 headphones in Korea and definitely give these a try because they bested a number of competitors at $150 including some more expensive AKG's. The thing is the 26p is very simple - not a lot of added comfort but I was so impressed I bought a second pair for when the day comes that the first pair break.

The 701 is very nice as well but I didn't spend time listening enough to know whether it would be a good rock can. Grado is also worth a shot.

Also consider investing in a headroom total bithead headphone amp - this is both a DAC and headphone amp and is portable and comes with USB. So you can run your music from your computer without the computer grunge getting in the way. It can be powered from your USB or uses 4 AAA batteries for portable use - it's about the size of the ipod classic but a bit fatter. This will help out those Mp3s a bit I'm sure.

They go for $150 and on par with any headphone amp I've heard int he $500 range but does more. http://www.headphone.com/products/he...al-bithead.php