I have the Ultrasone Pro 750 and these are really great for bass type music - electronic, trance, dance, anything really. These are pretty good all rounders too. The only downside is that they are can be sibilant and unforgiving with poor recordings.
You should also consider the Pro 2500/2900, which are the open versions of the Pro 750/900.
I will caution you, though, that if you are planning on purchasing high caliber headphones, then you will also need to buy an amplifier to power them properly and get the best sound. Also, if you source sucks (such as a crappy soundcard) then you will want to buy an external digital to analog converter (dac) to properly process the music.
There are some pretty good amp/dac combos on ebay for cheap.
If you want to explore headphones more, I would strongly recommend you to check out head-fi. There's a ton of headphone related info on there.