I noticed last weekend when I drove on my buddy's dirt road in Oregon after
a fresh application that the dirt really accumulated on the rear winshield
and it highlighted the pattern of the rain-x I put on. But then when I go to
wash it off, it is like there is wax on the car, it comes off real easy. i
dont know if this helps you without trying it out for yourself.

You live in a good area to test this product - so it really works for you.
But what about dirt and not just rain... does it keep your windows cleaner
so you don't have to clean them at the Gas Station..... and get your van all
mucky like Bill???