I have the entire set, and I think the ones with actual routines tend to stop and start too much to really have much impact. The third one (I think that's the one) with just dress up routines really isn't a workout at all since the exercise moves are things like "take your glasses off and toss them across the room."
At any rate, they are fun, but I think the 2nd one is the only one that really is a workout.