My SYS1 machines, AFTER some mods (especially on power supply board !) was EXTREMELY reliable at locations.
Let's talk about few thousands games-followed them back to the my workshop for general cleaning and changing rubbers (usually only that)
I have seen quite SYS1 machines - they have done over 100-150k games (even more !)
So, I can not agree with you that SYS1 is unreliable
Greetings from Croatia