Optimus Tracker user here as well. 3 months now, did various tests. Works as advertised. Highlights are...
> Nice simple user interfaces on web n phone apps.
> Alerts by email and/or text about 30 seconds after leaving geofence.
> Tracking stored, then uploaded, when mobile data is available if none is available. Only tested this for 20 minutes in a metro area.
> Choice of ATT or Verizon 4G SIM card, be sure to ask before ordering. if not familiar with this choice, Verizon coverage is better in rural areas.
> Cust Service/Tech Support competent and had easy access.
> Placement will matter. Surprisingly, our unit works in the engine bay in metro areas, haven't tried in a rural area yet.
> 1-month battery, and/or direct wire to 12V, and/or USB-C charging plug