Hi all, I have a room of approx. 12' by 14', and a setup consisting of 4x m3ti's for fronts and surrounds, along with a vp-100 and a yamaha rx-v657 receiver. I am now trying to decide on a subwoofer, and I was previously told that I'd get more bang for the buck with an SVS as opposed to axiom for the lower end subs...my question is as follows:

the svs pb10-isd is £470 here in england. a bit more than i originally intended to spend, but i'm told that it puts the ep175 to shame...for £500 i could have the ep350...slightly less amplifier power than the SVS, but a 12-inch driver. Which is the best subwoofer between the two? i'm more inclined towards the ep350 as i'm told that it automatically powers up/down when my amplifier is switched on or off, along with the fact that i'd like a full axiom house. if i do however go with the axiom, i don't want to have sacrificed any performance. i'm fairly new to sound systems, however i'm learning fast. any help would be greatly appreciated. thanks.