Hi Alex,
For what it's worth, I too am a huge music fan, from old school metal, classic rock, progressive rock and even country. I have had the EP350. Then later added a PL-200 for 2 subs.
Finally, I went with 2 EP500's, one in each front corner of my room. I was close to going with 2 svs subs, but with the Ep500's having DSP control I went with Axiom.
Prior to getting the the dual EP500's, I always felt like something was "missing", maybe not enough "tightness", not really sure, it's hard to explain.
I can tell you, for me, that feeling I had of something missing has been completely erased with the dual EP500's. BTW, movies are incredible as well. Just FYI...
Dana