The ScoopFree (SF), much to my surprise, failed the final cat test this weekend. Initially, I bought the SF and gave it a 20-day trial with my cats and stored it away while the cats tried a 20-day trial with the Litter Robot (LR). This weekend the cats could choose to use either the LR or the SF as the auto boxes sat side-by-side in the laundry room...
The first night, as soon as both cats saw the SF, again, they eagerly used it, welcoming it back into their world with poop. I thought it was all over for the LR. But I was wrong. This morning, Nuba who initially pooped in snow, peed in my leather couch, and pooped on my bed rather than get inside the LR, headed for the SF, got in, dug, sniffed, turned to the LR, sniffed it, climbed out of the SF, climbed up the step of the LR, got in, and peed and pooped... while I stood there watching slack jawed! Zen urinated in the SF all day... and maybe the younger cat did at times, too... I thought Zen might stick with the SF but tonight she got into the SF several times, dug, and left... the last time, dug, turned to the LR, sniffed, and climbed out of the SF to enter the LR to poop.
I was amazed... They don't need an electronic box to pee in crystals... They can do that in ANY box. I hauled in their old sterilite box, dumped the crystals in it, and started packing up the ScoopFree. It was getting quite late by this time and the cats came into the laundry room, climbed into their beds -- one on the washer and one on the dryer and watched me in my obsessive state with their litter boxes. They didn't seem too concerned as I removed the SF and they headed off to kitty dreamland. They have selected their auto litter box! I really thought it would go the other way...

Kitties: Zen & Ariel. Litter Box: Litter Robot. Remembering Nuba, Ceba, and Yang Su Ling.