Basically the title. I've got a 2009 Ford Fusion SEL with SYNC, Moon & Tune, the whole shebang. The car is my baby, and my mobile relaxation spot. I'm wanting to put a little money into upgrading the sound system now that I've got a new battery and alternator installed and she's running like a new car again. I've already installed subwoofers in the trunk, now I'm just considering going through and replacing the tweeters in the A-pillars and the four door speakers. But I'm curious if it's even worth doing that without putting in an aftermarket amplifier? Or alternatively, should I just stop thinking about component speakers and get a nicer head unit first? I hope this is the appropriate sub forum to ask this question in. Thanks for your time.