fluid film is good but there are better products available. i live in iowa which is as bad as any rust belt state for road salt, many of my friends prefer wool-wax over fluidfilm, says it is thicker, last longer & applies better. most the forums for trucks or 4x4 off roading say wool wax is better too. but either is better than noting or the spray on rubberized under coatings.
a somewhat new product from PB blaster has been getting excellent reviews and every one thats used it says its far better than fluid film.
https://youtu.be/NE1_EiZIVHs