I've got two eclipse 12's with a Fosgate bd1000 amp and six 6.5 MB Quartz and my system sounds great. The box is sealed in the rear bench and it's loud and has lot's of bass. The high's amp is a fosgate 500 watt 4 way. I also run two marine optima/ blue tops for the stereo alone and can switch to all four optima's if I want. I think it better to use the best equipment you can get your hands on and then decide if you want more bass. It's all about the combo and equipment that works well together.
My best friend had 2 12's in a 87 camaro that was the loudest thing i have ever heard. They were some old school JBL 12's with a crossfire amp in a huge box. The god damm thing would shake your filling's loose. And this was back in 1994.