I am not sure why some folks are such digital thinkers, the real world is not all 1 and 0's. I have used both methods, Zeps and machine buffing with compound. Both processes are a lot of work. It took several days to do a 19 ft FG boat with Mequires ultracut compound and a machine buffer. Some areas I had to use 800 and even 400 then 800 grit paper again to remove all the oxidation, stains and scratches. It was a lot of work but look nice afterwards. Boat was a 2002 that sat in the Fla sun 12 years. My MH is 18 years old and was always from Mass. and Ct. with little sun. Was able to hand polish up until 4 years ago. As an interim step I used the bar keepers friend 4 years ago to remove the oxidation then hand polished. 2 years ago I tried the Zeps process based on many positive reports on this forum. I was pleased with the results. My conclusion is this: I would not use the Zeps process except on an older highly oxidized surface. I think people put this on 5-8 year old MH's and it peels off because the surface is too smooth. I would not even think about it unless I could no longer get the surface to shine by using the Bar Keepers Friend first then a good cleaner wax. Both processes are a lot of work but I am older and have 4 Ti pins in each shoulder due to rotator cuff repairs. My son had to finish the buffing for me. So for older guys with bad shoulders like myself I would use the Zeps, if I was 50 or younger with good shoulders I would opt for the machine buffing, just remember that a good gel coat surface is only about .020 thk and you can burn through the gel coat into the FG if you are not careful. Also on non gel coated side panels(Filon) where you can see the fibers there is even less resin. Good luck and let us know how you may out.