I teach install of medical washers and sterilizers and 90% of what's installed is with pro press. If it's done right there aren't any problems that i've heard. I also teach soldering because you have facilities where they don't want pro press..
The water in my area turns copper to eggshells in record time. When your utility bills inexplicably increase and your concrete kitchen floor is strangely warm, it's time to be concerned. I have used PEX since it first became readily available. While I can't say that I have had zero failures, it has proven to be by far the most dependable choice for my rental homes and renovations.
Was that section of pipe exposed to an UV rays? That pic looks like UV damage. If so replace with that section with copper, you can use sharkbite fittings to join the pex to copper.
Not direct sunlight if that's what you're asking, this particular section was the hot water leg at the top of my HWH in the garage. Since there was no shut off valve I just put one in place after cutting out that pinhole.