Almost anything other than stock will sound better, even with the factory head unit. But wont the amped speakers be only louder and not more clear than being non-amped.
And do the 2000+ have 6.5" in the door?? Didn't know if they're 5.25" still or not.

They're either 6.5" or 6 3/4" in the front doors. If you go with an aftermarket Headunit with RCA outputs the amped system will be clearer assuming you buy a good amp and headunit. With the factory headunit, I'd imagine it'd be more clear and static free without an amp.

I am running the first pair in my car, and love them. They have great bass and they hit the highs pretty well too. I hear nothing but good from both speakers, I would suggest listening to both pairs before you make a decision. Whatever pair sounds better to you, you go with.

The door speaker are 6.5, I all ready checked on that. I did upgrade the 6x9
2 years ago 2 the pioneer 220 watts 3 way speakers. & I loved the sound.
Just looking 2 upgrade for more sound. I will post pic of the speakers.

I looked at all 3 speakers Infinity, bose, & pioneer speakers. & picked pioneer
due 2 the better price. I loved the sound of all 3. I think infinity had a more true
sound. & pioneer had more bass. & bose just cost 2 d@mn much but had maybe
the best over all sound quality.

Thanks everyone!