you what they say about the peoples opinions-- they're like a**holes, and everyones got one...(for instance, i don't like infinity stuff-- the highs are too harsh, the bass is too muddy, but bes says that he likes them...)
i will say that there is no perfect sub-- every single sub lacks in one respect or another, and is better/worse to different people-so determine what you want out of a sub, and go from there--even better, demo as many subs as you can at your local electronics store, and find one you like.
I've always had good experiences with JL Audio. They have a wide range of subwoofers to fit almost every system configuration. Reasonably priced (with the exception of the W7, that is), and built to last.
I've got a pair of Audiomobile MASS 2012 S24, one of which I used to use in a late-model GMC extended cab. Freakin' AWESOME is the only way to describe the build, power-handling, and output. I'm going to reconfigure these into home theater subwoofers.
The other one I have (but have never actually used, yet) is an AD (Audio Development) MM12 subwoofer. I've heard the separates (3-way system, which I also have), and I expect the subwoofer will be just as impressive. It's built primarily for sound quality and not sheer SPL, and looks like a piece of fine jewelry. It'll be a shame to hide it in an enclosure!!