Just bought this for our 8 month old kitten, who was very interested as soon as she saw it and now won't leave it alone! Also tried it out on two younger kittens who both went nuts over it. The toy is really well designed, can be assembled in a few different ways. The holes and slots in the track are the perfect size for cats to put their paws in to swipe at the ball, and although there are lots of points where they can touch the ball, the track is designed so it can't get out. The ends of the track are slightly raised so that the ball keeps moving for as long as possible after you (or the cat) set it going. You can really tell that a lot of thought has gone into designing this thing. Also the hilarious picture on the box is reason enough to buy it. Get one!