It is good, but it would be for 5 stars if it cost up to 35 euros. It does the same as a regular infrared thermometer with the difference that it lights up blue or red if the temperature difference is greater or smaller respectively than the first measurement. In conclusion, it is a fine thermometer, just a bit expensive.

Quite a good product, it helps me detect leaks in aluminum doors, areas that need insulation, floor-to-wall joints, etc.
Reliable, works for about 6 months with a 9V battery, instant indications, screen with good clarity. Worth it.