If your cat will accept this as part of her life, I like it a lot, my small kitty who died used it exclusively.
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The ones that attempt to scoop clumped litter have inevitably always failed me. If they scoop too early, or kitty has an unfortunate bout of digestive upset and loose stools, the mess the rake makes becomes ungodly.
I invested in one on kickstarter that has yet to deliver... like a year and a half ago.
This is not an automated box, but also is really neat, you only have to scoop poo out and replace pads and swap pellets every month or so. (But same thing if there are ever loose stool situations. You'll be dealing with a very unpleasant mess, so I would only do this if your cat is notoriously regular. But I've had great success with it too.)
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