I think the 2 EP350's will give you a better balanced sound as in less dead spots in the room, but the 2nd EP350 won't give you more or better bass in your prime seating location.
A single EP500 will let people in the next town know you're watching a movie. You wouldn't get the same sensation with 4 EP350's
My recommendation is to go with the single EP500 and use the sub crawl method for optimum placment. Trust me, you can't go wrong with 500 watts and DSP. DSP is great cuz you never have to worry about over driving your sub and damaging it, and that is very important.
Just make sure you have glued down all the china in the china cabnet before you put in U571.
Paul
