"Our almost three year old daughter loves the train. We have the track running around our Christmas tree, and she's been playing with it for two days now. Unfortunately, every time she stops the train without shutting it off, the wheels slip. She stops it just for a moment to attach an animal from her other sets, but it's long enough to damage the piece the engine is on. The teeth on the track are so shallow and soft that the every time the wheel of the train slips it smooths out that section. After two days of use, more than half the pieces have almost smooth areas. When the train cars have more weight than what comes in the set, it slips a little on those spots and wears away more of the teeth. It's a really fun toy but not built for how little kids use it. The teeth on the bridge are much larger and don't seem to have the problem.
If you do get this set and have carpet, we recommend using pieces from other sets to hold the tracks together."