scott

get the ep500
that is a big room and you'll really enjoy the added bass the bigger sub will give you.

you said you're also thinking about a vp150. if you dont have a center already, go for it. if you already have one, is it really that bad that you need an upgrade? you'll know if wehn you watch movies, you find it hard to hear the voices, or if the voices sound like they aren't coming straight from the center.