[Blind Driver]

Rain-X is a pita to use. A much better product is Castrol. It's located next to the Rain-X, it's in a purple bottle. Rain-X is rubbed on, wait for it to dry, then rub it off like it's a wax. I always have to go over mine 3 times before the streaking is gone. Castrol goes on like glass cleaner, no streaking.
Rain-X also make a washer fluid too. Works well, I also use it in my cars. It comes in Bug-off and an ice remover formula.
Use either on all your glass and chrome. Don't forget your marker lights too. Both will keep them cleaner for a longer period of time, and will help prevent ice from forming.

For those of you that don't know....both products will keep water from sticking to your windshield. At highway speeds (depending upon aerodynamics), you can turn off your wipers and watch the rain fly over your windshield upon contact. 8)

[Porchclimber]

I don't mind Rainx on mirrors but I don't like it on the windshield.
FYI I use a little bit of liquid dishwater detergent in my washer fluid to cut the salt and crap.
Works great.

[Splitter]

I had the same black streaks on my truck as well. I used goof off to clean the windshield off, and got new blades. I have not used rainX on my windshield since. I do use it on the side windows, and the mirrors though.

[cdltpx]

I have used alcohol to remove old rain X and wax from the car surface. Then after we are back to zero I repply wax and rain x. I have used both rain x and wax and it is true they both have about the same affect just rain x works better for me. :rock:

[slowmover]

I learned that the way to get RainX to work was all in the prep.

I used WINDEX (or any cheap alco cleaner) with #0000 steel wool; wipe vertically, wipe horizontally (using tons of cleaner) and then swirls.

The trick is to get into the edge seams as much as possible.

( I now use an anodized aluminum cleaner, a buffered acid safe on glass MARY KATE CLEAN & SHINE I get thru WEST MARINE)

Then, rinse with hose. And clean with INVISIBLE GLASS (aerosol can, not sprayer) and some microfiber towels.

I work over the interior glass pretty much the same way.

After I can find no problems, then I apply RAINX.

I use the I-G cleaner/microfiber from then on after using fuel island brush/cleaner.

Bugs come off very easily (Lousiana love bugs), and a new application of RAINX every so often.

I have no night-time glare (or blindness from sunlight thru the back of a fogbank); and I have tried wax, too. The first way works best for me. This was on trucks with 5-700,000 miles and what was probably original glass. Getting the crud out of the pits was what made it work.

I'll try the Aquapel.