Gonna bring this thread back up to see what sub the OP went with. I just ordered an unloaded Thunderform and a Polk MM1040DVC to replace two JL 10W1V2-4 currently powered by a HiFonics TXi-1008D. Unfortunately the basket design of the Polk sub hits the taper inside the MTX enclosure. Right now options are send the Polk back in exchange for something else, modify the enclosure or use on of the JLs.