Coming off a pair of SRH440s, which had a hinge break on me and are now unusable (super glue lasted about a day, may have to keep re-applying until I can replace them). I've also been through a pair of Grado 80is.
Presently looking for something in the middle. I loved Grado's clarity (though disliked its comfort. Neither the default pads or the replacement pads I purchased were particularly comfortable). Shure lacked the clarity but had a bit more power.
Sennheiser's seemingly out of the question, as you typically need an amp to power those properly, though their sound does seem ideal for what I'm looking.
Looking at the ProDJ100, but I don't think it'll hit what I'm looking for with bass. I like it punchy, though not overpowering. Hard to describe, I suppose. Not sure about the Portapros either. Need to stay under $120 or so, I think, preferably under $100.
I use my headphones for gaming (which means a bit of everything tends to go through them) and listen to hard rock/metal material most of the time.
I'd honestly go with another pair of Grado 80is if I could find a way to make them comfortable, but I'm also interested in something new.
I own a pair of Alessandro MS1s, which wont solve the comfort issue, but i like its signature WRT to Grados. 99$, as well.