Relabled audiobahn subs.........and like with anything related to audiobahn they probably won't last long and won't sound good (I have a set of Digital Audio aka audiobahn speakers that after 6 months of use being powered by a pioneer p770mp they're showing signs of dying and no I don't beat my audio equipment up).
But this is my opinon, if you think they look great or a buddy has um and they slamm or you're getting um for mega cheap than I say have fun and do what you feel is the best.
I frequent the Wal-Mart car audio section, and find the Dub subwoofer, 12 inch 500 watts i think. It is a very cheap looking subwoofer. It looks cheaply made and just doesn't have a very professional look. They have one hooked up to listen to and it sounds like garbage.. just my opinion. I would even toy with the idea of a Sony sub over this one.
Oh yeah... if you do end up buying the dub sub, please do us all a favor and trash the chrome dub rim speaker cover that comes with it. Uggglly...