My toyota dealership offered years ago a windshield treatment that would keep the car windshield
clear and you could drive in the rain even without wipers on. It seemed cool so I tried it. 30$ was
expensive for just one treatment but I was also blown away by the result. The windshield was just repelling water. At high speed
on the highway I would not need wipers. The water would just form little beads that would roll up the
windshield. At low speed one would occasionally use the wipers. Visibility was really good.
However this did not last long. After about 2 to 3 month I noticed tiny lines and scratches that were
visible on the windshield. The area where the wipers moved was visible when it was not raining.
It was like a strange haze and the sun would reflect on the scratched film.
Driving in the evening became impossible. The headlights of other cars would reflect on the scratches and visibility was really bad. It was dangerous to drive like that.
I tried everything to get rid of this film that the windshield treatment had created. I rubbed and cleaned the windshield
with soap, glass cleaner, alcohol, hot water,... nothing worked. This film stayed and I was furious. However
the film degraded further over the next two years and it started to disappear leaving patches where I could finally see something without the glare and the scratches. Eventually everything was gone but the car was basically unusable during the evening for a period of about two years.
I warned all my friends to stay away from this stuff. It was a scam. I was therefore rather sceptical when
Scotty Kilmer made this video where he suggested to use wax free nufinish polish to clean
the windshield: