I always love how everyone says the same thing "I only want a little bass, I dont want my trunk to rattle off"

Heres the order things go from here
Get something small and not very powerful, be happy for about a month.
Ride in someone elses car, and hear much better, louder bass. Get sad
Buy more and more and more till you throw it all in a river because it costs more than your car now.

Just keepin mind that you dont ALWAYS have to have the sub playing @ max output. I used to keep my ported 12a attenuated a bit because I didnt want loud 24/7, but when I did want it loud it was always there.