ive had my m50s for about a two weeks now and think they are great for electronic music. i was looking to upgrade from my px100 to a nice full size can, and after trying the hd485 and pioneer m390 I ended up getting the m50 and am glad I did. The bass is great, it extends really deep and has a good amount of impact. The mids are more upfront, which is nice for vocals and it makes snare drums really snap. The treble seems pretty flat to me, not bright, plenty of detail and is not sibliant unless its in the recording and even then they can be forgiving. The soundstage isnt huge, but its there.
There are fairly comfortable, a little tight at first, but can wear them for a hour before needing to give the ears a break.
I primaraly listen to drum + bass, house, and trip hop.
My source is a Onkyo DX-7555.