I'm owner of a few sub-100€ head- and earphones. Currently I've got the Shure SE215s, a Sennheiser HD439 and the famous Koss Porta Pro's.
I've had two other models, but their cable broke and they are out of use now. One of them was the Sennheiser HD 229 with a very nice clarity in the highs, and good fitment, but very little bass... The other one was the Sennheiser CX150. Some years ago, you could call me a "basshead". These IEMs haven't got anything but bass! Totally overwhelming ...
At this point of time, I use the Koss for hearing music outside, the Sennheiser HD439 for hearing music at home and the Shure for traveling and my IEM for loud places.
Got the Beyerdynamic DT990 Pro a few Months ago. It's just amazing. I'm driving it with my Fiio E11 and an onboard soundcard (shame on me) of my ASRock H77 Pro4/MVP. I love the sounding, the comfort, the soundtage and... well, everything ^^
I'm driving my headphones with an iPod touch 4th generation and a Pioneer AV Receiver VSX-322. As I said, I'm also using a Fiio E11.
As I said before, I'm not a "basshead" (anymore). But anyway, I'm listening to electronical music like dubstep or something like this. Still, I like to hear my headphone's full power and skill, and this is why I also love to hear some classic.