I did the front doors and posted in the other forum. For a budget install, I am very impressed with the sound quality with a powered sub filling out the low end. As mentioned, the doors do not have any appreciable low bass and that certainly should not be a goal.
I used Powerbass 6x9 drop in midbass, FaitalPro 3" mid with separate low pass filter, Kicker 1" Ti tweeter with inline cap,