JL makes great speakers. If you want to add a deck, My 05 had the factory Infinity system, When I put my deck in it there was no sound. I had to run speaker wire from the amps, or deck, to the speakers. My 04 did not have the factory infinity system, puting a new deck and speakers in that was strait ahead. I think the factory deck puts out about 5-10 watts, most aftermerket decks are 20 watts and up. you will also see a big difference in the size of the magnets in the factory and aftermarket speakers aftermarkets will be bigger, and able to handle more power.