The good is that it is fast, does not hurt, is not intrusive. My daughter could not stand rectal thermometers, and it quickly became a way of the cross when she was sick. The bad points: it is only fairly reliable: if we take the temperature twice or three times, it will never be the same and it can range from 0.5 ° C, or more. Always change the tip and strength, it also has a cost. Third point: I do the exchange after only a year of use because the device did not recognize the presence of the tip and no longer worked. Fortunately he is guaranteed two years. In short, the principle is good but if I had to buy one, I would not choose this model here.