I was there two years back.
It's very impressive, the three-floor Mont Blanc setup is cool (you literally can watch the whole thing from three different floors, with trains coming in from different rooms/areas). The impressive thing is also how they have made cars move without visible rails (magnets under the road I guess) as well as how everything has lights and there is night and day shifting in the different halls.
The fire-fighting they talk about is also very cool. The scenario starts with smoke coming out of a building downtown (with yellow light flashing in the windows). Then police cars turn up to set up road blocks (halting the traffic) so that a whole host of fire trucks with blaring sirens can get there from across a bridge nearby.
The fact that almost all figures you see seem custom-made is also remarkable - there is a stage with several hundred in the audience, and if you start looking you can see they are all doing something, being dressed differently etc.
The airport was not finished yet when I was there, but the Scandinavian vista was quite recongizeable, especially since they showed the Kiruna Iron mine which I've visited once.
A massive piece of work, definitely worth visiting if you pass through Hamburg.
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Griatch