I took my rears out and noticed a major gain in my sound quality. I also dropped they Hz range of the sub back, so it was far from directional sound. Now the sub actually sounds as if it is in FRONT of me, which is ace.
Id lean towards a different headunit, Id go eclipse (sp?), they really are tops.
And DO NOT FORGET FOR THE LOVE OF GOD, sound deadening. Make those doors deader than your great great uncles first gold fish. Id also stick to one good quality sub.
Finally, as much as you might like pinoneer, go listen to as many brands as posible, you might find as much as the pinoneer are good, you like something else much better.