I think I've tried just about every litter box on the market, lol.
My latest purchase was a Clevercat box, but I'm going to return it. It's too dang small! So I went to Fred Meyer today and bought just one of those big Rubbermaid Roughneck storage boxes and I love it! I swear this is the best litter box ever, definitely beats everything else I've tried. The cats have so much room to move around and dig until their hearts content.
Just curious what everyone else is using.