I’m not a fan of Rainx. I find it leaves streaks on outside glass when raining. Probably because it works into the wiper blade.
Same here. The only RainX product I use is their wipers. They wipe clean and seem to last the longest as long as you clean them regularly. A qt of denatured alcohol and a ton of paper towels was needed to remove all that crap.I tried RainX several decades ago on the outside of the windshield. I encountered the same greasy foggy surface film it creates, I have never used it again...