The kits are ideal for areas where the distance from the handset to the panel is excessive, especially for residences or warehouses that have gated entry as you are not required to leave your vehicle to enter. Setup is really simple using the SIM card and sending a sequence of text messages.
It is best to use a pay as you go SIM card with auto-top up enabled as then you will only pay for calls made rather than a monthly charge on a contract SIM (dependant on level of usage).
The system can additionally be used with a pre-existing SIM card which needs to be GSM compatible. Make sure to put the panel's number in your phonebook to avoid confusion and end up blocking the number.