Not sure about the best but a few of them have been mentioned on the forum; meguiars #7, aquapel (lasts longer but beads slower), the "nano" or ceramic coating.
Zaino is good stuff. I never had good luck with the longevity of the wax on the paint though. Seems to wear off quickly.Since '98, I've had very good results with Zaino and highly recommend it:
https://www.zainostore.com/
Becky, I prefer Zaino because it's not wax, but some polymer stuff that bonds with the clear coat at the molecular level. After applying Zaino, you didn't subsequently wash your car with dishwashing liquid did you? I know Zaino recommends washing with Dawn before applying their product, because it's caustic, and removes everything down to the clear coat.Zaino is good stuff. I never had good luck with the longevity of the wax on the paint though. Seems to wear off quickly.