Okay, so you've probably all read about Green Stuff more than a few times recently, but I'm going to go over yesterday's experience with the product.
My test subject, a '69 Dodge Dart, has the one of the most horribly neglected finishes which I have ever seen. The last time we can verify that this car was polished or waxed was some time in 1985. Now, since the car has a single stage paint coat, you can imagine the blue powdery mess that's covering it right now. I figured that if Green Stuff could make a dent in the Dart's paint, then I'd be impressed. What good is it to test out a polish/wax on a car that already has great paint, right?
Well, the results were in fact pretty impressive. Just a few drops on a cotton cloth quickly cut through all of the paint oxidation on the small spot I picked. While it didn't do to much for the fine scratches, I can't say that I would expect it to. There was a lot of oxidation and it quickly loaded the cloth I was using with a thick coating of blue crud. Additional product application would most likely work out a lot of the scratches and haze left in the paint.
By far the most impressive part of Green Stuff is the super slick finish it leaves behind. I've never felt any paint as slick as this is! I mean, this stuff is slippery! it'd be great fun to watch a cat try to jump onto a hood which had been treated with this stuff.

I'll be interested to see how long the slick finish lasts with all of the rain around here.
Here are a few photos. One of the hood which shows the over all condition of the paint before I did anything, and one of the small area I used Green Stuff on.
All in all, I'd say that Green Stuff holds great promise for use on regularly maintained finishes. So, if your paint is already pretty clean and doesn't require more than light polishing, give this stuff a shot.
