The principle is good but...
The idea is great but the quality of the product is poor. The inner filter grill regularly pops out and the tray needs to be opened to refit it which defeats the purpose of having a quick-clean litter tray. The plastic on the bend of the filter grill cracks, allowing clean litter into the collection scoop, and this has happened on both our original model and it's replacement, meaning that we're having to use duct tape to plug the gaps. It still needs to be opened every day to allow me to scoop out the small clumps that get through the filter grill despite trying it with both very fine and coarse litter. I don't think it's worth the money, but that said, our cats love it, preferring it to both open and covered trays.