does anyone have exp. with this sub MM12?

I have a chance to pick one of these up on the cheap and was wondering if anyone has any experience with them, if so was it good, do they suck? thanks

http://www.polkaudio.com/caraudio/specs/recent/mm12/

Sold many of them a few years ago and never had one come back. 1" baffle on the subwoofer and the correct air space. If its in good condition you should be very happy with it...