Don't forget, there are those with dedicated theater rooms that can place such a woofer but for what it goes for I think the buttkicker might still be the better product (goes lower and easier to place most likely).
I heard this woofer at my local dealer (he deals in Nht, Sound Design, Celestion, Onkyo, and Denon home audio and Clarion, JL Audio, and Denon car audio). When he had this hooked up as part of their display, it was crossed at 27 hz (he told me that in his opinion should never be crossed past 35...