I've had good luck with Zaino products, their ZCS Clear I've described to be like Rain-x on steroids
! I've also the last few years, been using Nano spray protection on our paint. Both Eagle 1 and now Maquiers, as I like to test new products. This also does a great job on the glass too. All the glass, not just he windshield, as it seems to stay cleaner longer. So whenever I get the ladder out to clean the windows, I grab both my cleaner, and also the protectant, and just do it all at the same time.
Best to all,
S