The new ones are different than the one I had but my HF one was utter junk. And it was back when they went on sale for $40 or something like that.I agree, harbor freight has non-contact IR thermometers for $30. It would be worth the money to try and validate the mag thermometer.
These seem like good deals for cheaper ones though, this is the one I got after I pitched the HF one https://www.amazon.com/dp/B00JCH2YJC/?tag=hearthamazon-20 it was under $20 and dual laser so you know how big your reading spot is (and its a very tight spot) wide range and different data modes, adjustable emissivity and all that.