Depends on your use of watches and the environment you tend to be in. If you are somewhere that allows you to see whether there it is day or night, than using 12 hr setting will work just fine. However if you're in a place that keeps you secluded and you are not able to determine whether it is day or night than 24 hr. setting will help you keep track of not just the time, but whether it is day or night.
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Depends on your use of watches and the environment you tend to be in. If you are somewhere that allows you to see whether there it is day or night, than using 12 hr setting will work just fine. However if you're in a place that keeps you secluded and you are not able to determine whether it is day or night than 24 hr. setting will help you keep track of not just the time, but whether it is day or night.