I just bought another Instant Vortex after the one I bought one year ago simply stopped working.  No power to it.  I bought it again because I really liked the one I had.  I used it almost daily.  I've stopped using my oven.  I am going to give it one more try.  I bought the metal one.  If it stops working again, I'll be forced, of course, to try another brand.  Things sure are not made the way they used to be made!