This has been working great for my cats, I needed another litter box in the front of my house and I wanted something that did not take up too much space or look like an obvious litter box.  Some people said their cats didn't like the curtain, mine don't seem to care either way. I don't know if the ionizer function is really doing anything, I don't notice any difference when I have tried it so I am giving this 4 stars.