Sub recommendation

I'm thinking about upgrading my sub (see signature). Should I take advantage of F&F or would I be better off elsewhere? An SVS BP-1000 might fit the bill, but 50% off on a DSW sound tempting. What would you do?
HT- Samsung PN50B860/Integra DTR 30.3/Rt55 Fronts
Rt35i Surrounds/Cs1000p Center/SVS BP1000 Sub
2CH - B&K MC-101 pre/B&K EX-442 amp/NAD 2400 amp
Polk SDA1C, Polk Monitor 7, New Large Advents and Polk RTA 8T
BR - Yamaha CR800/Polk monitor 5

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