We first discovered this toy at a home-educators resources exchange day, and I couldn't get my then 4 year-old son away from the table where Zoob was being displayed. So I decided I would get him a couple of Zoob sets for his 5th birthday (this one and the 125 pieces set) and we're not disappointed! He absolutely loves this toy, as does all the family, all the way up to grand-dad, who is 81! I've had a lot of fun with it too. It's a great way to play with my son, without getting bored or feeling I should be doing some housework instead. The wheels on the set are sturdy and work well and we can create an infinite number of machines, robots, cars, etc, especially if combined with a set of Zoob pieces. Once built, they can be played with, so you can create your own toys again and again! I can imagine my son building up on the 2 sets we got him and creating more and more complex models as he grows. This is even better than Lego (and we're big fans of Lego!). We highly recommend this set, or other Zoob sets.