i would stay away from the sony speakers s sound quality is crappy, pioneer is by far the best value (price vs sound quality vs spl)if you are going to turn your ride into a music box i would spend the extra money on the amps and wiring, it pays for its self in the long run. remember to look at the RMS on the speakers too. try to match these to your power source as close as possible.
pm if you would like a specific online store that has UNBEATABLE prices.
my set up cost me a few thousand dollars but the sound makes it worth it.
pioneer headunit
4 12" RE Audio subs
4 6.75' pioneer speakers
2 6x9' pioneer speakers
0/1 & 12 ga. streetwires
good luck to you bro.