Rain X isn’t what it used to be imo. I use it on my side by side and it seems to only last for maybe a day then it’s ineffective. I used to put that stuff on my car windshield when it first came out and it seemed to last through ten car washes.
Because it isn’t. The original was made by Unelko, it’s now manufactured by ITW, they cheapened the formula.
Unelko is still around and waited until their Non-Compete was over, they now make a product called Rain Clear. Likely very similar to the original. However there are other products out there that work as good or better.
I’ve used Aquapel with good results, however I’m unsure if it’s compatible with plastic.