I purchased a Littermaid Self-cleaning cat box when we got our cat thinking it would make the chore of cleaning the litter box less bothersome. It worked great for the first two months, the cat would use it, leave the box and several minutes later we would hear the rake start up and it would dump the waste into the container at the end of the box.
After the first two months the rake worked hit or miss, it would rake once in awhile, the remainder of the time it just sat there. I telephoned customer service and was told that the rake sensors were probably dusty from the cat litter and that I should clean them with a damp cloth. I attempted to do this and got them clean and shiny and still the box did not work. By this time 90 days had passed and the warranty was no longer in effect, I now have a basic litter box that cost me $100. The cat still uses it but it has not cleaned itself for several years leaving that task to me.
I do not recommend this product and have since seen many complaints similar to mine on other websites. I was told my someone that the New and Improved Littermaid still has the same issues. Hold on to your money this isn't worth the price or the aggravation.