Car paint prices WTF!

From my experience I would not say water is any better or worse for color matching. If you panel paint with it you are just as likely to get a mismatch.

Funny, we had a Sherwin-Williams rep in, doing a demo. We ran out of his special "Sherwin-Williams, water" so he just grabbed some out of the sink and told us not to tell anyone.

Worked just as well.