Because of the price, I debated on whether to try this for quite some time. One of my pet-sitting clients had one and it seemed to work great for her one older cat. I bought one when I had 2 cats and it proceeded to throw the poop across the room each time it raked across to clean it! It's really loud, too, and I could hear it in another room across the hall with the door closed. My cats went nuts and had to run in to check it out each time it came on, causing the timer to reset again if they got inside of it and the sensor saw them. I returned it when repeated cleanings didn't help the "throwing" (I thought it was just jammed with litter). After I got a 3rd cat and scooping became a huge chore, I decided to give it another try and purchased another one. It worked great (besides the still-present noise) for a couple of weeks, then it started acting jerky and getting jammed about every other raking. I tried varying amounts of litter to try to fix the problem but it would just keep raking and raking and raking until it finally stopped and "stalled" until it could be reset. Of course my cats really went bezerk when it continued to rake over and over for about 10 minutes. Anyway, use caution because it seems to work ok for some people but myself as well as a few others seem to have had some real problems with it. Luckily no one has seemed to have a problem returning or exchanging when they get fed up.