For my cat he used it right away. The self-cleaning feature is great to keep the litter fresher longer. Instead of every week having to clean the litter box, I can go 2-3 weeks. The crystals really do lock in odor and moisture. Definitely made my life easier by not having to stress over cleaning the litter box so much. Is great when planning a vacation as well! No worry about it going off while he's in the box either. I can even see how many times my cat uses the litter box! Simply hold down the reset button to start at zero again. Wish there was a way to limit litter when he leaves the box.