Okay, which would sound the best with my Rockford Fosgate power 501BD amp with two sealed enclosures at .55 CF each.... the Fosgate P210S4, P210D2, or P310D2??? Im not sure with my mono amp at 500W which would sound the best. The guy at the store recomended the P210s4.... And the reason for Fosgate is because of the costs I can get...Will I notice a big difference with the DVC over the SVC? and once again I dont want to underpower what I buy and Im not good at matching the specs up..Thanks for the advice...