Originally Posted by Unscathed
I am used to sound systems in cars that are closed up.. not jeeps... it's a different world
Not necessarily true. While Jeeps aren't as sealed or "soundproof" as other vehicles, with an appropriate box/sub combo, you can make a Jeep sound pretty good.
For the sake of full disclosure, I run 2 10" Infinity subs in a hardtop YJ, which makes a difference. With decent sound-isolating material such as Dynamat or cheaper knock-offs, you can make the sound in a Jeep sound as good as most other vehicles.
With all that said, if you're running with a soft top or run topless often, it won't make much difference, so don't waste your money on my suggestions. Just enjoy the boom you get from a down-firing sub and call it good.
And for the music you said you listen to, go with 2 10's. It'll sound more defined and will keep your hearing for another year or two longer than with 12's...