ported vs sealed... i used to be a ported guy but when i switched to sealed i was much happier with the sound, much clearer and accurate. and ported will be louder but honestly when it gets to the point all you can hear is the sub, its much better for sealed.

dont get the kicker, get a used ED sub if your getting a 12" get this link: YouTube - Elemental Designs 13Ov.2 Subwoofer
the 13ov.2 i have the 15s and they a hawt (watch the 16ov.2 vid its more impressive) link here:ICIXSound.COM Forums - 13ov.2 Dual 2 Ohm 100.00 Shipped
heck of a deal if he still has one. look around icixsound fourms, thiers always good deals for ED stuff. the nice part about ED subs is they require not very much air space at all.