In a previous thread (Good wipers - Legacy), Rain-X was mentioned. I bought some and applied it today. So far, the results are good. I've have yet to encounter rain, but I can see the difference when just applying washer fluid. The liquid sure beads away quickly.
FYI: Here is how I applied it.
The temperature was about 7C.
I washed the windshield (front and rear) and rinsed well. Three times, each time scrubbing to make sure it was clean. Then I let it dry and got rid of any remaining moisture with a dry cloth.
I put some Rain-X solution on a clean dry cloth. I rubbed in into the window much like one would apply wax. Circular motions, making sure to cover the entire area. I did the front window one half at a time. I let the solution dry and it came up to a slight haze. Then I repeated the application. After it dried again, I wiped off the haze, or perhaps more correctly, rubbed it in, with a clean dry cloth.
I repeated the process for the other half of the front window. I did the entire rear window all at once, but using the same method.
I'll probably do the side outside mirrors and the side windows tomorrow.
:)