I’ve just replaced mine, having used it constantly for the past 3 years. Best gadget I ever bought. I live on my own and never use my main oven now. She should have a book with it telling temperatures for foods. Chips with just a dash of oil are lovely. I use mine for more or less everything and have adapted recipes to use in it. Just tell her to thoroughly clean it each time, particularly after cooking chicken, sausages or chops in it otherwise she will get a lot of smoke coming out of it.