Bests & Worsts Reviews from Amazon

At first, I thought this was great, and even bought a second one for the two new 6 month old kittens we just adopted. It definitely works as advertised and filters through the cat litter leaving clumps behind, BUT the problem is it is just TOO SMALL even for kittens. As soon as they were introduced to the rest of the house, and our other fully grown, but not very large cat they rejected these litter boxes in favor of the other cat's larger litter box which doesn't have sifting pans. Three other things: 1) Don't expect this to sift out every little bit of feces. Smaller bits inevitably make it through the sifting process. Not sure there's anything you can do about this problem as even scoopers have this issue. Sh*T happens! =) 2) If the manufacturers made a bigger version of this, I'd definitely buy it, but they really need to stop calling it "large"! 3) The other suggestion I have is that the addition of a guard or even deeper pan to keep the kitties from pushing litter out of the side would be great.