I had an EPA for my husband, shared with my son who lives in the same village. Our other son would take over if anything happened to either me or my son.
It did come in useful when my husband could not write any more, and could not sign his name. It was also the case when the medical profession thought that he would not be able to remember what he had agreed to the next day.
Whenever we went to hospital appointments, I was always grateful when he had to go to see a doctor, and I could have time off, even if it was just sitting in the waiting room, knowing that someone else had taken responsibility for him. However, soon I had to go everywhere with him, except into the scanner.