I used the modded SR-80i that I had when I was going to uni last year. Squawked like a parrot at everyone that went by, but boy did they sound good for rock and metal.
If I were in your situation, I'd go for a pair of CAL! (Creative Aurvana Live!) and never look back. They're closed, so they don't leak much, but isolate enough so that when you're listening to music you can't hear most* of anything. My modded D1001 (which are share the same drivers and housing as the CAL!) sounded quite a bit better than a stock D2000.
As far as sound signature is concerned, the they are a little on the warm side. markL modding helps tighten the bass, thus bringing out the lush mids. The highs are pretty good, but not the best I've ever heard (in comparison to the various Grado cans I've heard and my DT 1350). For the price, you can't beat them for the sound they offer.
* if someone is yelling at you, you'll hear them