I have a handful of the DS3231. I set the time in the house, and it runs for close to 8 years with incredible accuracy. I use the internet NTP time service to set the time; it's a couple of wires and takes 2 minutes. I never touch it again for 5 years. When I connect a couple of wires and replace the battery (maybe 3 years early), I can make a time adjustment at that time, but I almost never need to.