Tidy Cats Scoop for Multiple Cats with Tidy Lock is what I use. That Tidy Lock is immediate odor control and it truly works! I have three stinky cats so it's been a constant search for something that works because one of the boxes is here in the office and I was being stinkied out of here. I started using this and haven't changed...probably won't either.
It's even easier to clean than other clumping brands...don't know why but it is.