I have the Fresh Flow Deluxe. I decided on the deluxe for a specific reason, but I can't remember what that was now The motor is very quiet, unless it gets low on water (that's happened a couple times, when the cats drink a lot or the water evaporates faster because of weather, etc). My cats probably drink twice as much water with that than when they just had their water bowls. I still have the bowls around the house, and they do use those too, but they just love their fountain.