Like Seth said, most every sub sold retail does not have the same quality/outptut to $$$ ratio that internet vendors deliver. As for the Hsu vs. SVS, that is a no brainer. The SVS is a larger, more capapble driver. The Hsu is no slouch but it can't hang. Stephe Ponte did a great job designing that driver and Tom Vodhanel did a great job designing a sub around it.
The only times I see someone use a Kicker sub in home theater is when a car audio guy has an extra one and decides to build a sub. Otherwise there are many other more capable, better sounding drivers out there. Since you have already been to Acoustic Visions, check out Exodus Audio, Dayton Audio, CSS and Soundsplinter. Other subs not listed but worthy of checking out are Fi Car Audio, Ascendant Audio, Sound Solutions Audio, Sundown Audio and AE Speakers.
When Kicker "introduced" the square sub, they were being built in the US by
Credence Speakers and the original models are still available. Kicker, like most companies, has moved to an off-shore build house.
According to
this manual, the L7 15" has 16.3mm of xmax as opposed to the 75mm that you mentioned. Linear xmax is much more important than mechanical excursion (xmech) and it should be stated in one-way, not two-way so that all speakers can be compared equally. The xmax king right now is the
RE Audio XXX series with 54mm. It's an amazing speaker using split voice coil technolgy to lower distortion. It also has an equally amazing (STICKER SHOCK!!) price tag.
-Robert
