From the build quality, to the bass, clarity of the sound, and noise canceling, these phones are amazing.
I have at home a pair of HD 600 (plugged only into a FiiO E10, but still) and I was blown away by the IE 80 + E7 combo. If it wasn't for their noise canceling, I would have ditched the HD 600 in their favor (at least until I get a new DAC); alas, I need to hear what happens around me while at home.
If you're in doubt about these ... go buy them, they're awesome. Oh, and if you're a bass head? They got you covered as well.