The turbo scratcher is simply a plastic circular base with a ball that rolls around the track on the outer edge. It has cardboard corrugating medium as a clawing area on the inner part of the circle. It is very simple, yet highly effective.
I don't know why, but this has been a success with every cat -- young and old -- that I have seen around it (15 different cats). Once they get the ball moving, it really flies around the track! The younger cats manage to pull the ball out of it within 10 minutes, but they have a blast in those ten minutes. The smartest cats realize that it is more fun when it does stay in the track, though. A word of advice: don't put this in or near your bedroom. If your cat feigns disinterest when you first bring it home, watch out if you are a light sleeper -- a couple of hours into sleep you will wake with a start to the sound of the ball whipping around the track over and over and over again.
The two 14-year old cats that I currently reside with love this thing. They aren't usually interested in toys (in our presence), but did manage a very disinterested tapping of the turbo ball if they were sitting on the mat anyway. These senior cats' main interests in the Turbo Scratcher are 1) using it as a meditation/sleeping spot --- it is so much more sophisticated than sitting ON the floor, and 2) actually scratching it (and these two are declawed!).
The fact that the ball comes out of the track so easily is a small disappointment (granted the cats do have to grab it with both paws to pull it out). You can easily pop the ball back into place, but some of us have too many places that the cats can hide such a small item.
Besides that, after 4 years, all our cats still use it daily. As a toy, well, its success may depend on the age and personality of the cat. As a scratching post, however, it is the only one I have ever bought that all the cats consistently used as such (though they do still get use out of the couch, too). I have been a "cat caretaker" for many many years so I do have some experience with several different types of scratching posts and this is by far the best.