I think the EP175 would be fine for music (unless you are really into pipe organ music), but it just doesn't reach down low enough or with any authority for movies. I Auditioned the ep175, 350 and 400 at Axiom in their 20 x 12 x 8' room and the ep175 just didn't have any rumble. The EP350 did a very good job on both music and movies.
I suspect that the EP350 would be enough sub for the vast majority of people out there. I get down to ~21Hz in my room and that is good enough to really add to the movie experience.
Its integration with my mains for music is flawless. Though I have not had a chance to listen to subs like the SVS PB10, my understanding is that they are a good budget sub for movies, but give less than ideal performance for music. It all depends what you want.
