The name brand PCs are a hassle in many ways, but the parts do get added scrutiny. The problem is that some of the parts are very expensive to replace if you want to replace problem parts with the name brand originals. Apple is an absolute nightmare for people who want to fix their own computers and some of the other brands are not a lot better in that respect.
True that about fixing Apples (and some others). I think the only Apple thing I've done is to upgrade memory size in an older Mac Mini (I think that can't be done on the newer ones).
I believe that Apple's main draw for people is the "Turn it on and get to work", controlled environment, no "I have to find a better Driver", etc. environment.
I have an M1 Mac Mini (believe they now have an M2 version) and it works fine (I have to admit that so many years of Windows for me makes using it challenging at times -I think sometimes I'm just getting too old to learn new tricks).
As to the Cooling Systems, I initially had the same concerns. When I realized that I was going to have to upgrade the failed one, I was a bit worried.
But it's pretty simple process, and inspecting it, the only way I can see for it to be messed up is to have cheap crimps on the liquid lines or to install incorrectly and bend the lines improperly.
I didn't mean to imply that the IPower PC was a total no-go, just that there were some problems. As You say, Brand name parts can have problems also (sometimes shipping problems too - once got an expensive Intel chip that came loose in it's plastic holder and all the pins on the back were crimped over).
However, for myself, after buying the IPower, and considering my past knowledge/experience, I would research and build any future PC myself. Lots of modularity that wasn't there long ago, which makes assembly much easier.
At any rate, I hope You find, and build, exactly what You are looking for and get all the (virtual) flight time you want/need.
If you pass over the Gulfport MS area, wag the wings to say hello 8-).