The B&W PV1 measured very poorly. I would not consider that a contender (esp. given the price). The DD series is on par with the Ultra, but only the DD15 and DD18 (not cheap).
The smallest sub SVS makes is the SB-12, but it isn't going to have nearly as much output nor extension as the PB-13Ultra. The next biggest sub is the PB10NSD, but it doesn't have the looks. Honestly, I think you would need to get the Ultra if you want SVS. I think with the metal grill it will look really nice.
SheepStar