Head's up for my brothers and sisters in arms (DOD civilians too I think), before you make a final subwoofer decision check out the prices on Velodyne products on the AAFES/MCEX/NEX online catalog. I was surprised that they even carried Velodyne subs. They not only carry them, they have the best prices I've seen with no taxes, and free shipping in CONUS (limited time offer I think). I just bought a DD-12 for $1300 delivered. They have speakers up to 12" in the DD, SPL and DLS series. BTW they also have some good prices on Yamaha, panasonic, and limited Denon gear also. You have to set up an online account, but for the savings it's worth it.
jason a
pioneer elite vsx-74 (for now)
panasonic s-77 dvd player
def tech UIW 94s fronts and center
def tech UIW 83s surround and rears
velodyne DD-12 (on it's way)
xbox 360