I have an ep350 and it shakes the room - I have no performance issues what so ever. I think many people that post to this board have built their system buying piece by piece because of the cost of these great speakers - Hence people getting different subs. Also too, if you get the system complete, you get that 5% discount. Some threads I read stated that when the EP350 is calibrated, they could tell no difference between the HSU and the EP350...