I think I've used every automated cat box on the market, and a few not on the market lol.
My current setup is four litter boxes, two upstairs and two downstairs:
Two of these Clevercat boxes
A Container Store sweater box that also serves as a portable litter box
and a Cat Genie.
Duma is the only one that uses the Cat Genie. My ragdoll doesn't like it, I assume it's because he's kinda big for it. I have the globe top for it to better contain the litter pellets that scatter everywhere, but we cut a big hole in the top in hopes making it less claustrophobic. Duma's only 10 months old, he isn't very big compared to what I hear about other SVs. Oh, and it doesn't scare either of them, as there is a delay as to when it runs (or you can set it at intervals), but one time when I manually ran a cycle Duma was watching me and became fascinated by it.
I don't find that the Cat Genie uses much water, and it doesn't seem more expensive than any other I've used. But I do find that once or twice a year it stops working, in which case I take it all apart and clean it with vinegar and it starts working again. Even with that, the Cat Genie is the least amount of maintenance of all that I've tried.
If I were getting another automated litter box, I'd probably go with the Litter Robot. It works pretty reliably, my biggest complaints were the dust (it tosses the litter around creating a cloud that leaves a layer everywhere), and cleaning it every few months, there's a lot of parts to it.
My next-best favorite (or maybe tied with litter robot) is a box called Scoop Free, but you have to use crystal litter with it, and Dante doesn't like crystal litter at all, I think it's rough on his delicate paws. I haven't used it since I got Duma, so I'm not sure how he'd take to it.
HTH