I have a raytek at least 12 years old.
Seems pretty accurate, unless the srfae is highy reflective.
it will read 122f on my aluminum radiator's top tank where a Ktype thermocouple taped to it will read 196f.
If I put a piece of black gaffers tape on the top tank and aim the IR gun there, it reads the 195+f.
They are useful for hunting for the highest temperature, just do not think that the laser pointer is where it is takng a precision reading of that red dot. It will average the temperture within a certain radius of that dot.
They are cheap enough now to be well worth having.