If you read the Zep/Red Max Pro Application Process, you might become discouraged at the amount of work needed. The post describes what is needed if you have an oxidized and dirty RV. You will need to scrub off that old, oxidized layer regardless of the final coat you chose so applying Zep is no more difficult than any other wax job. As described, there is one added step. You need to use TSP, dilute ammonia or some other wax stripper to remove any previous waxes. That additional step is pretty easy, just use a long-handled mop and go over the surface a couple of times.
Doing a good initial job of surface prep will mean your Zep finish will last and save you many, many hours or days of work over the years.
I did not try Zep on a new RV with a shiny gel coat. When I started mine was a few years with minimal chalky oxidation. I did have lots of black streaks below the gutter spouts, windows and wherever water flowed off the RV. Zep has all but stopped that streaking.