To get back on my original topic, I finally bit the bullet and ordered a new sub. An SVS PCi+ 20-39 is on its way. I know, I know - I'm going to get flak for not getting an EP500. I'm sorry.
I'll defend myself by saying that I've wanted an SVS sub for years, and $800 for the SVS is already bending the budget a bit compared to the $1,300 for the EP500 (believe me, I've had a $1,0xx outlet EP500 sitting in my cart for weeks....). Besides, that $500 difference now goes in the "I need M80's" fund.
A big thank-you to everyone that has steered me towards the sub upgrade route. I look forward to joining the 'I have a real subwofer' group.