Well I scraped out all the ProFlexRV that I put on about 6 months ago. It pealed, shrank and became hard as rock. No flex.
I bought a tube of Big Stretch (Lowes) after reading product reviews and watching their video.
https://www.sashco.com/products/big-stretch/
I wanted something that was going to flex with this rolling earthquake called a Montana.
Goes on easy. Drys clear. Good adhesion so far (1 week).
Let's see how it holds up.
Again I only used it to touch up a few places. 95% of the original factory sealant is good.