From my past experience of maintaining and repairing electronic data communication equipment and computer systems for a major telco provider in Australia I would say the failure rate of electronic equipment is fairly small compared to the number of operational units working 24/7. Product reliability has a lot to do with the quality of the electronic parts used and quality assurance testing done after the manufacturing process. High operating temperatures can reduce the operating life of electronic equipment. Other sources of product failure can be attributed to mains power surges caused by lightning. So having an electrical surge protector in your mains power switchboard is wise. I also use power surge protected power expansion boards on all my Spooky equipment and laptops. Another typical point of failure is dry solder joints. Another typical source of failure is switch mode power supplies and they tend to fail after 4-5 years of operation. Manufacturers of electrical equipment usually provide a mean time between failure (MTBF) rating for their equipment.
I have been operating one XM generator for nearly 4 years not stop without any failure so far. In regards to Generator X I have only had one for about 2 weeks so we will have to wait and see. As both generators use switch mode power supplies I reckon this will be the main failure point after 4-5 years of operation.
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