The litter tray liners have a major design flaw - folded pockets that trap substantial amounts of the unused cat litter - when you tilt the tray these fall into the waste tray meaning that you lose loads of clean litter each time you pull the lever.

The door system is also quite nice as my cat doesn't love being in an enclosed space for too long so we keep it open for her to stick her head out when she uses it. Me preocupa la durabilidad del mecanismo pero por ahora me parece suficientemente slido para mis gatos. To refresh the litter pan, all you have to do is pull down on the lever to activate a seamless and noiseless process that quickly and efficiently sifts and disposes the waste for you. Thanks to the self-cleaning system of the litter tray, it will stay clean and fresh without the need to remove the litter daily.When cranking, the clumps of litter are supposed to funnel towards the middle, and then subsequently be deposited into the bottom tray when the gap between the swinging shelf and the face of the unit is large enough. Even the 3 kittens that we adopted (not simultaneously) started using it straight away after we showed it to them (with the lid open at first because they were too weak to push it to enter). I previously bought another litter box with a similar sifter built in but the problem with it was that you have to roll it upside down to sift it which still requires effort and strength that I don't often have. Another issue with the clumping litter and these types of sifting mechanism is that the urine litter clumps can sometimes stick to the tray so I have a flat litter scoop nearby to scrape off anything stuck to the tray.

This means the bowl won't rotate since cranking now just swivels the arm, rather than acting as a lever.

The litter clumps get stuck to the litterbox itself making it impossible to dispose by a simple turn of the handle.

None of them are good enough to warrant anything higher than 1 star, but it's worth talking through them anyway. This is very problematic for this product because in addition to the "trapped to the side" issue in a previous criticism, when large clumps correctly fall into the middle, there isn't enough space for the clump to fall into the tray below, unless you're willing to let unnecessary amount of unclumped litter fall in too. There is also a large entrance for cats of all sizes, with a swinging door that closes on its own, ensuring that the unit is sealed shut, further controlling the spread of odors and dust. We also found that the clumped litter adhered to the bag and required manually removing - which kind of defeats the purpose of the whole idea of the tray really. Apparently Catsan Clumping Litter was the litter of choice as the litter used on the CatIt demonstration video is only available in the USA.To summarise, this box saves me tons of time daily, as I don't have to be "hunting" for the nasty bits hiding inside the litter, and there is NO WASTE of clean litter whatsoever. By over filling the bowl (due to the lack of information in the manual telling me the right amount to put in), after many cranks, the "plug" for the arm itself has warped the surrounding socket. Making it unbearable and wastefull by changing the plastic bags everyday instead of the recommended every 2-3 days. It would also need extra effort occasionally as the used litter wouldn't always fall in the right place so I would have to reach in and contort myself to get everything out. However, we found out that we could line the drawer with the (larger) base liners instead of the (smaller) drawer liners; when the time to change the litter comes, the larger bag allows us to empty all remaining litter into the drawer and dispose of it in one go.

The whole unit is rather large, and my kitty has had no problem so far with the space available inside. Yes, clean litter does go in the bin, if you don't follow the instructions and put litter ABOVE the line that is clearly in there. This means I could during the week transfer clumps and waste from the lower tray to the Litter Locker without having to make trips outside (no issue with odour as it is actually well designed) before then transferring the good remaining litter back to the top tray (as mentioned, in fairness to this litter box I probably had overfilled it - but equally sometimes the mechanism needs more of a jolt and so good litter could be lost; just an inherent limitation of the design. The plastic hinges on the sieve/sift attachment were so flimsy that they kept dropping off whilst Mum was changing the litter. This was sorted very easily with communication and replacement sent once damaged item received back.There is also a minor problem as you have to use clumping litter with it which will sometimes stick to my Luna's stinky butt and back legs/ paws but she's easy to clean even though it's not her favourite thing for me to do. It's my understanding that you need to have two litter boxes for one cat and one extra for each additional cat in a household.