I recommend this to EVERY person who I know has a cat, and also when people stop me in Walmart to ask me about litter (you'd be surprised how many times that happens--apparently I just look like I know cat stuff?).
It was the best $300 I ever spent. I've had it about 8 months now and no problems so far. As someone said before you get a 2 month money-back deal if your cat just won't use it, and it also has an 18-month warranty, which you'd never get with a Littermaid. What I've heard so far is that Littermaids usually last between 1 year to 18 months before dying completely. Litter Robots have a reputation of lasting 3-4 years at least.
I have 5 cats using one Litter Robot, no backup boxes. When I first got it, I had 3 cats, and 2 of them used it right away, it took less than a week to get the third one to use it. The two cats I've gotten since then had no problems using it the first time in the house. I only have to change the bag 2-3 times a week, and the only problems I ever have with it are my own doing, when I forget to change the bag in time and a little bit of poop smears around the globe, but I'd still much rather wipe a little bit of poo off the side once in a while than scoop scoop scoop.
I could rant all day about this thing