Itasca/Winnie side panels cracking - Vetrolite option

More facts and theories on the Vetrolite failures:

CDI, applies only the full body paint for Winnebago. CDI uses Sikkens & Sherwin Williams products.
Winnebago does the partial paints, CDI believes Winnie uses DuPont (now called Axalta), single stage with a clearcoat. (A Winnie CS rep told me they use Imron 5000 with clearcoat for their partial paint schemes.)

CDI has refinished vetrolite. (Other brands of siding have failed too)
CDI applies 3 heavy coats of 2k primer, sands this, then sometimes applies a sealer before the basecoat (color), then 3 coats of clearcoat before sand & buff. Cost for this type of refinish for entire RV is $14-18k.
"The finish may later crack. (The cracks in Vetrolite are likely to enlarge.)"

CDI was very helpful and knowledgeable. From other posts, forum members have been pleased with their refinish quality and speed,

After 7 years outside mostly in Florida sun, the partial painted areas are excellent. The white of the front cap is good too, just the normal dulling expected with a gelcoat. Strangely the rear rear surface is excellent too (Maybe not Vetrolite?)

The Vetrolite sides where not painted look terrible as posted above. The area below the Sunova decal we removed shortly after purchase is still excellent. Theory: the decal may have allowed the surface of the Vetrolite to fully cure before exposed to UV or ozone. If so, the Vetrolite on RV's that saw little sun, or were garaged for the first year (or were made from older or better panels) might not fail for a long time.

Any experience good or bad refinishing failed Vetrolite sides would be appreciated.

My thought for now is to use the brush/roller technique to repaint the sides with a 2k single stage urethane.

The auto industry makes car finishes that stay outside year round and they still look good for many years. It can be done. I haven't waxed a car in years.

You are right about how tough UV is on vehicle paint in the SE and SW states, and that inside storage makes a big difference.

But consider the cost. If inside storage was only $200 per month, in 7 years the out of pocket would be $16,800. Plus the aggravation and time of driving to and from storage every time.

If a company produces vehicles that often stay outside, the finish should last more than six years. That's fairly easy to achieve with the 2 component urethane paints that have been available for the past 40 years, especially on vertical surfaces.

Spotrot, that is good advice about storing your rig indoors or covering it up from the sun. Those direct UV rays from the sun are very harsh on paint, especially year around in the Southwest States.