I've owned both of these subs in the past. They're older models, that's all. SB12 is a really good sub. I highly suggest getting two, to help ensure a balanced in-room response. The PB12 is a big time performer. Not quite as tight as the SB12, but FAR more impactful and can much more easily pressurize a room. What's really impressive and somewhat usual (especially in this price range) is that both subs have a flat response far beyond 120hz, which makes blending with various main speakers easier. Both subs truly are scorching deals at their respective prices.