Stink Free Litter & Litter Box Spray has two purposes. One: it instantly eliminates odor in cat litter, and two: it keeps scoopable litters from sticking to the litter box.
I used it primarily for the second purpose. If you've ever spent time trying to scrape the bottom of a litter box clean, you will fall in love with this stuff. Plastic litter trays get scratches on the bottom that can make it hard to get them clean. If you spray this on the box before adding the litter, it creates a protective coating that prevents this problem. Litter box cleaning becomes a quick and easy task. (Yes, really! This is good stuff!)
The first purpose, that it instantly eliminates odor in cat litter, is not very useful because the spray itself stinks. It's much worse than cat poop smell, and that's saying something. I suppose if you're into the whole idea of fighting fire with fire, then the noxious smell of the Stink Free Litter Box Spray gets points for being strong enough and terrible enough to make the cat odor seem tame. I let the cats poop in their box inside the house, but I took this spray outside and far away when I was using it. I wish I could have used it without being there. It's noxious and powerful and makes me wish I was smelling poop. I've never used anything that made me wish I was smelling poop.
To its benefit, if people come into your house and smell it, they will probably think something like, "Wow, what kind of chemical weapons are these people building?" You may prefer this to people thinking, "Ewww, their house smells like poop." If so, go ahead and give it a try. I have to admit that I didn't use it for this purpose, so I may have missed something. Regardless of the smell, however, definitely get ahold of this stuff if you're having trouble getting your litter box clean. It works.