I sprayed a fender on my Trans Am back in 1991 using one of these. The paint went on OK and I did it with a single aerosol unit, but don't expect spray-gun results. You'd need to color-sand it a little before buffing. It's not really orange peel, it's just not perfectly smooth. The guy to whom I sold the car crashed the balls off it about a year later, and no paint jumped off. I still have a piece of that fender in my garage.
My biggest concern is that it coats evenly and doesn’t look striped. Metal doors and oil based paint. I’ve already painted 4 sheets of plywood with that paint and its got to look better than rolling it on like I did with the plywood.
