So, we have this for our son just in case he gets separated from us when the family is away. The phone, SMS and chat function works very well. We have a SpeedTalk SIM card and it works in about 15 minutes. There is an application called "SeTracker" which you also need to configure the phone.
I would recommend disabling the call pad, limiting to certain known numbers in contact lists, and blocking unknown incoming numbers for security reasons.
One thing we never understand is why the clock isn't accurate? In the SeTracker app there is something to get the time zone. We set it to GMT+5 for the Eastern US time zone, but the time is off by a few hours? That's pretty funny for a smartwatch! Since we care more about the phone/call function than the time function, we dropped it. We even try to manually set the time in the watch, but it will be reset to the incorrect time.
Still, as a "tracker" and phone for a child in an emergency, I'd say it's fine.
Update 4/2/23: I figured out the time issue. I have set the time zone incorrectly. Unfortunately in the SeTracker app they only have GMT -5 and it doesn't say "USA Eastern Time". The time function therefore worked correctly.
Useful