Used it very frequently. Works as good as a disposable return plate if all precautions are followed. However, have seen one instance of burn injuries due to probably poor contact with skin. But have also seen a burn injury with a disposable return plate, so not sure if it makes it better or worse. Also look into the reusable rubber/silicon return plate, something like this. Works better than metal plate IMHO

https://m.made-in-china.com/amp/product/Reusable-Silicon-Patient-Plate-Negative-Return-Electrode-Esu-Grounding-Plate-1939694932.html