I'm leaning towards the dt770, but i'm also leaning towards the Vmoda m100 and the Yamaha pro500 both of these mostly because of portablility and because of the removable cable.
CRAP!!! I really wish i could listen to all the suggestions you guys have given me -_- It really makes it hard to choose.
Portability king from these 3 == V-Moda M100!!
It has its own case, removable cables, you can optimize and change the plates, etc. etc.
Personally, although COMFORT is not the best for me with the M100s (nor Yamaha Pro 500s), both VModa and Yamaha ARE better sounding (to MY ears) than the Beyers...