Unreliable, the readings have nothing to do with reality. With a fever of 38.5, it showed 34.8 in a second measurement of 36.5... completely wrong!! We sent it to our technical department and they told us that it works just fine, we just have to clean the sensor with a cotton swab and alcohol after each measurement. It still gave inaccurate readings. Also, when you have a sick baby and you wake up in the middle of the night to measure their temperature, it's not possible to constantly clean it. Not good at all and very expensive!!!

I have the XIAOMI ihealth and the measurements have been accurate for 4 years. This one gives random results. Usually, it shows 35.6 to 35.9 in forehead measurements. As for the room thermometer, it doesn't convince me of its accuracy, although it may be better for object measurements. For a branded product, I think it's disappointing, even though I bought it very cheaply (25 euros including shipping costs).

26/1/2022
OK, AFTER READING THE COMMENT AGAIN, I HAVE TO SAY THAT I TRIED WHAT I READ AND I'M COMING BACK WITH A NEW REVIEW.
I cleaned it with a cotton swab and pure alcohol, waited for it to dry for a long time, and the readings went up to 36.3 - 36.4.
Two days later, for the first time in years, it showed me 36.6.
I still have the lowest rating because I'm not yet convinced that this will stay and it's unacceptable that I bought a branded product that didn't work and there were no instructions for it. Let it be written in big letters that it requires initial operation and frequent cleaning.
If it continues to work properly over time, I will change the rating.

I still consider the XIAOMI ihealth the top thermometer, which is confirmed by the hundreds of thousands of sales it makes in countries like Europe, the USA, etc.
A look at the websites (com, de, es, uk, fr, etc.) will convince you.
I would like to draw attention to the price difference for the ihealth, which ranges from 115 in Greece to around 24 in France...