5th_Ghostbuster,
I agree with Flasken and Duncan about the Beyer 250-80. Great set of cans. Todd from Headroom recommended them to me for some late night gaming. At the time I had a newborn and I did not want to disturb the baby or my wife. That was almost 2 years ago. I am a proud owner of the 250-80. Great construction. I flew to NYC for the Hi-fi show and slammed the Beyers into my backpack, no problem. My son has dragged the Beyers around the condo and they still work perfectly. The cord can be replaced with a couple of turns of a screwdriver. The isolation is great, not to the level of Etys (but what is?). On the plane I did hear the engines, but I did not have to crank my Discman to obscene levels to enjoy my music. The velour pads are very comfortable, the only drawback is they may make your ears warm after extended listening (1 1/2hours).
As for the sound... Great bass not as low as the vaunted Sony V6, but not as boomy IMHO. Not as punchy as my 325s, but just right for the music you listen to. Massive Attack's Angel is a great track to listen to with the Beyers. They tend to be on the warmer side of things. That's not bad, just different. Even though you can drive these cans with your portable, an amp brings the 250-80 to another level. I have 3 JMT built CHA47s, a TA, and other amps. The bass becomes tighter, the highs more detailed and crisp.
The Beyers will be more expensive, but they will grow with your new found hobby (upgrade-itis - new amps and sources). These are great home cans that can be taken on the road (though they are not necessarily portable).
You can't go wrong with the other cans mentioned. I highly recommend the Beyer 250-80.
Regards - reynman