Here is something for all of you to consider. I owned a restoration paint and Body shop for 38 years and have heard all the issues. Here is the scoop on longevity of the clearcoat and a reduction in chips/chipping. There is no easy way out and it is pay now or pay later.
First the clear coat issue: If the surface clear coat is failing and it fails for only one reason, assuming the surface it is being applied to was properly abraded and the color coat was still within the "paint application window" is a lack of mill thickness. Simply put the painter did not apply enough clear. All of the manufacturers state that a minimum clear coat thickness for a 5 year finish is 2 mills. That said 3 mills will get 15 years! On a base coat clear coat finish only the clear carries the UV protectants. Folks it is all about money and there is no way for you to tell how much was applied by looking at it! There is a tool out there for measuring this dimension on steel bodied vehicles, I do not know if it works on fiberglass.
Now the chipping issue, we all have vehicles today that have plastic bumper covers of one sort or another, do they chip?? No, they do abrade some, but all in all look pretty good for a long, long time. Have you ever asked why, likely not, it is just that way right? Nope, there is a reason and it is not the skin material but the "flexible" agent added to the clear coat that in effect, rubberizes it. It is called a "flex" agent. Without it, if you bumped the bumper skin on your car, the paint would crack if over flexed and that does not amount to very much deflection.
There is absolutely no reason the front of the coach can not be painted with this additive in the clear coat. One reason a shop would balk at doing this is purely the technical skill of the painter. When this agent is added, the tack time of the applied material lengthens, allowing for a greater chance of the preverbal "run". For those that are not familiar, it looks like someone laid a clear worm on the painted surface or another description, the paint sagged before it set. These things do not just happen, they happen very slowly and are easily missed until to late. By adding the flex agent, it adds resiliency to an otherwise relatively brittle surface, backed by an even less resilient surface, hence the dreaded chip. The only way one would know this flex agent was added would be to put your finger nail into it and a slight mark would be evident and then would disappear with a little time. It will take wax and it will polish just like the rest of the car.
The simple reason the roof radius clear coat on all the coaches fail is as discussed, a lack of clear coat. It is not going to be seen and it just is not that important in the big scheme of production things. Scuff it very well with 3M Scotchbrite and if that does not remove the flaking clear, use any pointy object as a mild scraper and some air. It will come right up, then the Scotchbrite to lightly abrade the surface. The paint color should remain and apply 2 wet coats, or three and believe me it will last and be repairable if a limb tears the fiberglass as one did on my coach. If you put any coating on that surface like that discussed it will be a real problem to repair. It is however a great idea in theory.
Line-X or Rhino Guard on the front is a terrific idea, until one considers the difficulty incurred repairing the cap, matching the remaining surface in texture, thickness and color if damaged. I have to admit, I have seen some applications that looked really good and quite professional. I have seen other that were abominations that would have been fine in the bed of a pick up. Once on, and it is an "industrial finish", there is little choice as to whether or not you can live with it. You did it, you get to live with it, like it or not. Paint it, you can change it and if I looks unsatisfactory the shop at the very least will work to make it right.
Please keep in mind that this is all from personal experience. I hope this helps make a decision and thanks for the opportunity to add to the conversation.
1999 Safari Continental Panther Gold 425 CAT C12
1965-1970 U.S.Navy Naval Air Helicopter Inst Instr
TrailerToadw/24 ft Feather Lite & 1955 Porsche an
ATV, & an Old Town Kevlar Canoe, Solar Promoter, Generator delete, Dry Camper