I guess that depends on the individual. I'm just wanting better overall sound quality with a bit more impact from the bass than what the Bose offered. I think one 12" will be plenty. I can make the car rattle with this 10" if I dial up the gains.
I finally got it hooked up late last night to see what it sounds like. Even though my box doesn't meet the minimum volume specs, it still hits hard, more than I want or need. I've got it dialed down quite a bit for my tastes and until I can fine tune the LC6 and the amp settings. As for the overall sub sound, don't know if should sound any better if it had met the internal volume specs. But I do wish I would've just gotten an 8" instead. it probably still would've meet my needs/requirements and my box would've meet the 8" volume specs.