Seems to work fairly well at removing water spots.

It is not harsh. Will not harm a coating. It will not perform miracles. There isn't a product that can remove any heavy water spots. I owned a black car. I cringed every time it rained.

I should have taken the description more literally. This is good for watersports before they've formed... but then, so I'd a dry towel. I'm not convinced this isn't just deionized water.