Question about Laserliner ThermoSpot Pocket

Good day,
We have compared this tool with an expensive laser liner and the tolerance was up to 0.4° C. Otherwise, this laser liner is a very good tool in our heating service. Do we need it daily...

The tolerance is higher at low outside temperatures. We have used it as a fever gauge for entry checks. Up to approx. 10 °C outside temperature, the tolerance was 3 °C, after that it was quite accurate. We have checked it several times with a mercury fibre gauge.