At first my cats were skeptical about using the. Scoopfree self cleaning litter box.  It came with the box and the crystal litter. Just put it together plug it in and wala clean box.  After a while the cats got use to using it and I decided that anything to help cut down on seeing or smelling the odor is great.  The only issue I have is the cost of the refill boxes.  They were more expensive than I would normally pay for regular scoop away litter.