I used to have 2 10" JL W3's and it seems like it was louder than my 3 W6's. I heard this guy playing his system loud and when I asked him he said he's got 2 12" Kicker SoloBarics using an El Cheapo amp while I am runing my subs with a Phoenix Gold ZX600ti. I bought my subs used about a year ago for $350 and selling them for the same price while the Kickers are new for $400. I really want to get W7's but the damn subs(s) are way to priceyfor me. As for the trunk space, I'm not gaining any space since I mounted my amps right on the floor.