I had a hand me down RoboLitter for about two years. It worked great, but as soon as it began stopping on occasion (I’d have to reboot) I got rid of it. Now I have another brand which was highly recommended by two YouTuber who test cat things. Both liked the one I have, especially since it’s NOT cave-like which my cat didn’t like. My sitters have had no issues, but then, I’ve only had it under two years so far. I do have a regular sitter box for the “just in case” moment though.