The HD555 are open, so scratch that off the list. If you need some portability too, then I'd take out the 449 and Audio Technicas as well since they are all large and do not fold or collapse in any way to facilitate transport.
If you like the look of the 750, other DJ headphones might be up your alley. They all offer the same type of form factor with good durability and isolation. Check out this review...http://www.skratchworx.com/reviews/sh_srh750dj.php
and click the drop down menu for a bunch of others to compare.