Yes, those UPS's are great. After a PC died due to a power event, I got a UPS for the new PC. It can run my PC for up to 15 minutes on battery, which is generally more than enough, because the overvoltages, undervoltages, and outages generally last only a few seconds. In the last 12 weeks, I've had 3 power outages totalling 7 seconds and 6 undervoltages totalling 18 seconds.
Sometimes power outages occur because so many people are running air conditioners during hot weather that the power companies are overwhelmed. But I have a deal with the power company that helps with that problem. When I got central air conditioning installed, I got a lower payment rate by agreeing to let the power company put a device on my AC that allows them to alter its timing as needed to avoid peaks of the total power demand. I don't notice any effect, though.
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