I've always wondered just how you get the naughty child to sit/stay on the naught chair/step. When ds was a difficult toddler if I'd told him to go to the chair he would have refused (and had a tantrum) if I had picked him up and put him there he would have run off (and had a tantrum). I could have made dd use one, but then she didn't really need to (as evidenced by the fact that she would have sat and stayed on chair chair).
My facebook had mud kitchens advertised on it recently. Looked very cool, I think my two would have spent much happy time playing with one.