For $175 you won't find a much batter sub woofer than the Skar...For $250 brand new with warranty you definitely won't find a better sounding, more reliable, more underrated sub than an SA-15.
That's not "forum boner" or "nut hugging" I respect the hell out of what Jacob does and I know he doesn't just pick some Chinese garbage out of a catalog and stick some Sundown stickers on it...Sundown is as legit as they come, and with his attention to detail, and his drive to develop new things, Sundown will one day be the Rockford Fosgate, or Pioneer, or any of the other big players we all love to hate.
In closing...The SA- series of subs is amazing in every aspect...You want to spend $500 a sub? Oh they're out there too...