I've used not only the Meguiar's kit, but other Meguiar's products as well.
First - my coach is a 2003 Winnebago Adventurer that I've had since brand new. It's now garaged when not in use, but it wasn't always so lucky. For the first 3 years it was outside all the time in the intense New Mexico sun, and I never did anything but wash it, so by 2008 it was looking pretty bad. The roof is fiberglass, and was very chalky - there was a spot where the batwing antenna shaded the roof when down - that spot was still nice and shiny, but everything around it was dull and chalky.
The front and rear end caps are painted white, as are the 2 doors and the slide-out surrounds. Being painted, they have stayed white while the adjacent fiberglass had yellowed significantly. And the compartment doors and everything around the lower perimeter of the coach are painted tan, and are still in good shape.
There are lots of decals over the coach, and they are still in good shape - there's one spot that's a little faded, but otherwise they're good and I want to keep them that way.
In 2008, I decided that it was time to do something to clean up the outside. I first tried to do one side of the coach with some ProtectAll Oxidation Remover by hand. It helped a little, but doing that much acreage manually was too hard on my hands. And, despite my best efforts, I couldn't get enough pressure for long enough to really remove the oxidation.
So, I took the next step and got a Porter-Cable Dual Action polisher, an assortment of polishing pads, and the Meguiars kit. And I went to work on the roof. And, though it came out looking much better, no matter what I tried I couldn't get the area around the antenna to blend in - it improved from a 1 to a 6, but was still nowhere near as white and shiny as the spot under the antenna. So I ordered some Meguiars #91 - their most aggressive compound for gelcoat.
But I found that working on the roof was good - it gave me an inconspicuous place to experiment. When the #91 arrived I played with different combinations of materials, pads, work times, techniques...etc. What seemed to work best was 1-2 applications of #91 depending on the severity of the oxidation, then 1 application of #49 cleaner to help clean up any of the #91 that was left, and then the wax. From my test areas, I didn't see any improvement from the Polish, so I didn't use it. Then one application of wax.
Then I next tackled the drivers side of the coach. I did pretty much the same process as I did on the roof, but I did tape off the decals with blue painters tape. Like with the roof it looked much, much better, but still not as white as the painted areas. And working between the decals was tough, but I did find some 4" pads for my machine that made it much better.
For the painted areas I got some Meguiars #50 1-step cleaner/wax. Those areas didn't have any oxidation problems, and the #50 worked fine.
For the past couple years I just used the #50 cleaner/wax on the whole coach. It certainly saved a lot of time, but after a couple of winters in Phoenix the whole coach needs the heavy duty work again.
This time, I'm going with the #67 compound - I found the #91 a little difficult to work with. But I'm going to try a more aggressive pad, though. I'll use the #49 as needed to clean up after the #67. And then I'm going to try 2 coats of wax as recommended on the Meguiars site for extra protection, especially on the side that gets blasted in Phoenix. And I'll still use the #50 on the painted areas.
And I'll still tape off the decals. When you think about what's going on - to remove the oxidation from the gelcoat you need an abrasive compound that removes defective material to get down to clean gelcoat. Not something you really want to be doing to the decals.
Kinda a long-winded response, but...
Pat & Betty
2007 Tiffin Phaeton 35 DH / 2015 Jeep Grand Cherokee
Formerly 2003 Winnebago Adventurer 33v / 2002 Jeep Liberty