Rob, I don't agree with your statement about Armor All. I know it is not made for paint, but when it dries, it is hard as a rock. It dusts very easily too. You have to be very careful with it, because it will remove paint. I only use it when I can't get the paint to shine with wax. Also, I use it for inside trains, so no UV yellowing occurs.
As for WD-40, I don't really know. When I use it on non-train items, it never seems to dry and is hard to wipe off. So, it can definitely trap dust in that situation. It works great for polishing brass though!
George
