Just my twopence thoughts:
When I first got my macpro (nearly ten years ago), whenever I needed an upgrade I could get an official Apple compatible UG from Apple which was 100% compatible with ‘zero’ problems.
One of the reasons I moved to Mac for reliability.
It was only many years later when such upgrades didn’t exist, I had to get alternatives (i.e. ssd/gpu).
When I get a 2019mp, I will most definitely get any upgrades from Apple to ensure complete compatibility and reliability, since such upgrades are available. I would feel getting ‘pc’ components would be asking for problems, as seem to be evident in other threads.
Anyway just my personal thoughts......
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