Rain-X is the shiznit!  I've always used their products and just found a great new use - the inside of your glass shower doors.  So instead of having to squeegee before you get out it just all rolls away!

No the cleaner doesn't. In fact it will remove the slick stuff from a rain-x'ed window. However sparying it on a window coverd in dried on bug guts, let it sit for a few minutes, and they wipe right off. So after you use it you gotta re-apply rain-x. I usually don't use it on the front window. Once the front gets dirty during the winter I clean it real good and re-apply rain-x every now and then. Plus I use the wiper fluid, which does add more slick stuff. So usually I don't have to clean the front window the whole summer. I mostly use it for the inside of the windows on the car. Plus its quarenteed to be window tint safe.

One thing about Rain X . . .

Once applied, it needs to continued to be applied.
It bonds and changes the surface of the glass.

I get this from my cousin, who has a PhD in chemistry, esp. in a field related to the chemistry behind Rain X.  (Edit, 6/29-> his focus is on chemical polymers, esp. reactions and fusion/fission of those polymers-> which is what Rain X is/does.)
Also, he uses it and loves it.

I have used it in the past, but don't right now.  I have been thinking of starting up again, but will shortly being replacing the windshield on my xB (see post on cracked windshield).

I just wax my windshield when I wax the rest of the xB. Seems to work well for me.