I have now owned 2 versions of a self washing cat box: a Litter Free, and now a Cat Genie. The Litter Free, while not perfect, made me appreciate how nice it is not to tend a litter box. However, that unit had plenty of flaws, and a newly formed company engineered a better unit that fixed a lot of the issues the Litter Free.
I purchased the unit in September of 2006. I am on my 10th month. Up until recently, I was not the happiest person with the unit... I had a lot of clogging issues. Had I given up on the unit a few months ago, my review would have been very mixed, with the unit failing to process its daily duties a few times a month. However, I knew the company was working on some improvements to the most common issues, and my patience was rewarded (more on this later).
If you read the other reviews, you probably have an idea how the unit works. Up to 4 times a day the unit will clean the box. First, the stool is removed by a scoop. The stool is dumped into a processing unit. The litter box is filled with water, which also fills the stool processing bin with water. There is an impeller which spins the stool around the processor, that dissolves the waste, and then the waste water is pumped out through your sewer connection. The unit is filled with water and flushed several times. During the last flushing, a sanitizing solution is dispensed into the water. Once that water is removed, the litter is dried, and the process is done. This takes about 30 minutes.