For goals, I want a system with sq 90% of the time, and spl the other 10%. My install right now is pretty basic, with reference series alpine coaxials in all four doors running off my alpine 9886 and pxa-h100 then through the factory amp under the back seat. An RE SX15D4 wired @2 ohms running off a kicker kx1200.1, in a box that is too small, doesn't have enough port area, and is tuned too high. I also have an alpine 10" flip down dvd player in the ceiling. The dvd player is coming out since i don't use it. The door speakers will be replaced by Focal 165 a1 components that i already purchased. And the factory amp will be replaced with an old eclipse 3242 that i also already purchased. The kx1200.1 is being replaced by an saz-1500d that i just bought, and the sx15 will be going in a properly spec'd box very soon. For electrical I have a kinetic hc1400 for a main battery installed with 4 gauge power wire. I'm adding an hc 800 battery in the back with the amps, changing out all the 4 guage for 1/0, and doing the big 3. I know the sx isn't an sq sub and will probably be replaced later. Maybe with 2 12" FI Q's. I'm also ordering up some more fat mat. I think this setup will keep me happy for a while. But i'd eventually like to do an active setup, with some better mids. I only bought the focals because they were too cheap not to.