I can confirm that the balls now and then get stuck and need a little push to roll on, what the children but not identified the least. I think it even made them fun to push the fixed hanging ball with a ball our successors, to let them roll away again from the top, or to push a finger through the opening. Now, 2 months after the birth has confirmed to me my sister that her daughter still very happy to play with the ball track.
So I think that they, even if they are not perfect in the eyes of funktionniert us adults but is a very nice toys, where children have a lot of fun. Despite or perhaps even because of the errors.
Addendum (20:12:12): The bullet train is now for 2 years in use (that actually in use and is not only in the rum corner) at 2nd child now and it still looks almost the same as on the first day - only 2 balls come are lost :) Therefore still 5 star and absolute buy recommendation.
