I'll agree with Mad O' Cat Lady (great name!). By far, the CG works well for most people. The only problems I've experienced have been clogs and impellers issues. The clogs were solved easily by banging the output tube on the floor (usually once does it), and the impeller issue would probably not happen with the new impeller design. The clogs also may be solved by the new impeller.
Personally, I loved crystal litter. Since both my cats will use it, it's my choice for a manual litter box. I just don't see the advantages of the ScoopFree. First, having such ridiciously priced - for how long they last - trays is just a scam. I know, people have invented permanent trays, but this is an adaptation made by the consumer. Second, I want the cats' poo to stay in contact with the crystals for quite a while before being scooped out. That way they dry out and don't smell. Or don't smell so bad (I don't know, I have no sense of smell... I just know wet things tend to be smellier than dry things). Mostly, though, I never minded scooping out poo. Pee clumps in clumping litter are a pain, but I don't at all mind scooping out poo from crystal litter. What I hate is lugging up bags of litter to my apartment all the time and cleaning and replacing the litter in the litterbox. So, for me, the CG is best.
One cat refuses to use the CG, but this is an issue you have with ANY automatic litterbox. Or actually, any kind of litter. Until we're able to reason with our cats ("Really, Fluffy, this is better than the manual box. You'll have clean litter every time. Just try it!"), this will be an issue for every litterbox on the market. Actually, I probably could get this cat to use the CG, but I'm just not conerned about it as she is ill with cancer and doesn't have much longer before... well, you know...
I mean, I'll just say that I have little to no electronic/mechanical repair knowledge, and I'm able to keep my CG working. For this to be a first-run product, I've had very few problems with it. The CG customer service people are very nice and helpful, so I hear. Really, I think it comes down to what you want from your litterbox. While I think the LitterRobot and ScoopFree (replacement-tray-scams aside) are quality-made products, they simply don't meet my needs. If you think the CG is what might work for you, don't hesitate to try it. I mean, it has a 90-day (or is it 120 days?) return policy.

