I HAD THE SMALLER VERSION WHICH WAS GOOD BUT MY CAT GOT BIGGER AND WOULD NOT FIT ANYMORE. SO I HAD TO GET A BIGGER ONE. THIS IS GREAT NO MORE SCRAPING THE TINES OR SIDES. VERY QUIET. THE RAMP DOES MAKE IT HARD TO EMPTY THE WASTE CONTAINER. I USE THE CONTAINER OVER AND OVER UNTIL IT GETS SOILED.