I have been pretty happy with my Bose AE2 until I compared them with my old HD595's. I'm appalled at how I had forgot how good the Sennheiser's were. However the Bose's do have one advantage: comfort and light weight. I'm now looking at a REAL upgrade and have narrowed my selection to either Sennheiser HD650, Beyer DT990 or Denon AH-A100. Which one of these offer the best comfort? I listen to various kinds of music from classical to electrical genres and I like bass in moderate amounts.
For amping needs I have Fiio E7, but I'm planning on getting E9 to accompany it.