ok so I found out my car uses:
2--4x6, and
2--6.5 speakers

I don't know anything about car audio so,
1) what brands give the most bang/buck? I'm not looking to spend a whole lot of money, like <$100 on 4 speakers.
2) will it be necessary to completely rewire the door/rear speakers to get the best performance or should I just reuse the original factory speaker wiring?