I am certainly not trying to argue with anyone at all, but I am 60 years old, and have been cleaning/detailing vehicles, from simple wash jobs to full 4 stage wet sanding/buffing, cars to tractor trailers, for over 45 years - 15 of those years as my only occupation either at car dealerships or my own business, and over 30 years of doing it evenings/weekends - and I have a couple comments about what people said about RAIN-X:
I must be lucky when it comes to RAIN-X windshield washer fluid because I have always used it, and I never had a washer pump plug up on a vehicle. The people that don't agree with this statement are going to say that it will if used long enough. The company I work for now bought two Ford F150's from me - a 2011 and a 2014, both trucks I had bought new, kept for 2 or 2-1/2 years, putting 20-25,000 kms (12-15,000 miles) on each. The company still has them in daily use, with 275,000 kms on the 2011, and 235,000 kms on the 2014. The 2014 I drive as a company truck, and use pink RAIN-X in it all summer every year.........no pump plugging yet???
As far as using RAIN-X repellant on the windshield, again the 2014 has had it applied regularly since new (windshield has been changed once in 232,000 kms due to a rock breaking it) and I don't see a problem with long term use???
I WILL NOT DRIVE WITHOUT IT!!!!!!! I live in Atlantic Canada, where we see summer temps from 40 C (104F) to -40C (-40F) in the winter, and everything from severe rain due to hurricane remnants, to heavy snow, to freezing rain, etc., etc.
As far as I am concerned, RAIN-X is the best thing to make driving in rain, snow, the spray off vehicles on the highway easier and safer than anything I have tried. People will probably laugh when they read this, but I could, and would if someone wants to wager LOL take the wipers arms off my 2019 RAM and drive in any weather other than summer bugs.