I'm buyin a new sub considerin a few different options. Prob around 1k-1500 daily. Thinkin about RE SX, FI B(T)L, Q or DD 9300 series prob 15". How much difference in a 15" or 18". I never ran bigger than a 12". My friends got a Fi Q 12 (BP) boxed and all for $250 so idk if I can pass that up. I'm open to suggestions. Thanks all