Hardware durability

I am looking for pc and motion controller that will be as durable as fanuc, mitubishi ect. I repair cnc equipment daily and if you consider the environment most of these machines work in I find it amazing that I work on 20 plus year old machines that are steal making money another question I have will linuxcnc run that long without updates

We have a 36year old Fanuc controlled machine still soldiering on. But nothing lasts forever, and a PC is certainly not an exception to that. That said, I just pulled an OLD dos PC off of a cnc router (and it was still working), and replaced it with a linuxcnc PC. If that new PC lasts half as long as the old one I'll be plenty happy. That old machine was running an old 200mhz Pentium PC that had been running more or less trouble free for almost 20 years. Every couple of years I'd have to dump/blow out about a half inch of dust accumulation. Pretty impressive life span for an ordinary consumer grade PC. While the possible improved durability of industrially hardened electronic equipment sounds appealing, remember do you want to be saddled with what is basically an ordinary PC with a huge price tag 15-20 years from now, or replace a basically generic/inexpensive piece with current tech when it finally kicks off in 5-10 or more yrs.

Hopefully the PC industry has moved beyond the capacitor problems that plagued PCs 5 or so years ago.

I am considering using Linuxcnc for a nonstandard machine it will be for sale as a start up company this product very interesting to me because I don't have Lay out thousand dollars but if it won't deliver reliability like the major manufacturers I just can't go there I have to spend the money with the big manufacturers

For the most part Linuxcnc is as good as the hardware you install it on. If you are concerned about software reliability, as long as you choose a mature stable version Linuxcnc is relatively bug free, Some times with large major revisions, there can be some teething problems, version 2.7 is a good example, the new tool-planner that was introduced with 2.7 caused some small problems and it took a little while until most of the bugs got shook out. Now we are at version 2.7.6 and it seems to be pretty solid. I've been running 2.7 on several high production wood carving machines in our factory since it came out, (the new tool-planner was a huge speed improvement for wood carving) and one of our machines has been using Linuxcnc since EMC2 version 2.3 (back in 2011). I would expect the next major release to also have some teething problems because it is going to have some very large changes with the addition of the JA branch but I will still likely upgrade, because I crave the new features.