I have used it for many years and it is useful. It is good that you do not want to purchase frequently, so it is a problem that you do not want to become a product that has been sold as it is in trouble.
Even professional work has the best usability. I will buy the same one again if it drops or breaks. Even in terms of price, it is cheap to disqualify from things with unnecessary functions recommended by other goods stores at a pretty low price.
In order to measure the voltage drop when the extension cord was used, it was necessary to make a take out receptacle for measurement and a female, but it was easy to measure with the auto measurement function.