I have used Zaino Z-12 Glass Polish on hard to remove spots on the glass on several cars and it works extremely well. My X5 had a film on the windows when it was delivered that would not come off with any amount of glass cleaner and elbow grease. I used the Zaino Z-12 and it was gone instantly. This product also removed acid rain etched spots on my Mercedes E55 and left the windshield looking like new. Here is the description from their web site. I also use their Z-2 and it is the best polish I have ever used.
Z-12 Clear-View Glass Polish
We searched for years trying to find a glass polish that really works as advertised. Frustrated with the results, we decided to engineer our own. Introducing Z-12 Clear-View Glass Polish™. Formulated with mild abrasives, Z-12 Clear-View Glass Polish™ deep cleans and polishes all glass surfaces with ease. It quickly removes acid rain spots, hard water spots, road film, stubborn bird stains, and that annoying interior glass film. Z-12 Clear-View Glass Polish™ is so effective, it even removes fine to medium scratches. We have yet to find a stain that Z-12 Clear-View Glass Polish™ did not remove from glass. It leaves glass crystal clear and sparkling.
Code: Z-12
Shipping Weight: 0.72 pounds
Quantity in Basket: None
Price: $13.95
http://www.zainostore.com/mm5/mercha...Category_Code=