Oh yeah - I forgot to mention this. I saw the link for the Cat Genie and I will tell you this. We tried a "flushing" cat box several years ago. (I think at the time we had 4 or 5 cats). The concept was great, but there were things they needed to work on. We returned it and got our money back.
First of all, it took some getting used to for the cats. It had this crystal kind of "litter", and they weren't actually able to cover solid waste. Also, it was noisy when it "flushed". But, the worst thing about it was the odor. It would take a few minutes for the "flushing" to start, so in the meantime the poo is just sitting there, not covered. Then, when the water would start to swirl through to wash everthing down the drain (it was connected to the washing machine drain), the odor was just awful!! Even with the special (expensive) enzyme odor killing liquid you had to add.
Maybe they have made improvements since that time, but I can't imagine it being that great.
Just my two cents worth!
We did have one of the giant automatic litters boxes, and I think they work really well for 1 or 2 cats, but our crew was working that thing to death!!