DS has a train set and a small breakdown set. He plays with it for about 2 days then it goes away for another month or two. He's always excited to see it back, but on day 3-4 he starts getting destructive with it. His playing has changed - from just playing with the train, the people now talk to each other and move about and seem to have some sort of story going on. It is good for his imagination - but then again, he's the same with his brio set and his duplo people!