I've used many glass cleaners as well including Sprayway, Stoners Inv. Glass, Cosco Brand and so far the best cleaner I've found is:
30% Isopropyl Alchohol (80% Concentration) / 70% Distilled Water Blended and used in a nice sprayer.
The other trick is a tightly woven cotton cloth which traps dirt and doesn't lint. Griots sells some nice cotton polishing cloths perfect for cleaning glass.
For shows I also purchased plastic handle which holds a cotton and microfiber bonnet to reach into the edges of the front/rear windows, works like a charm.
