My kids love trains and we have miles of wooden track with buildings etc
We bought this for Christmas for our 4 year old. His older brother has the "normal" lego passenger train and they both seemed to enjoy that last Christmas.
I was slightly worried that the new duplo set would be ignored, however they have played with it every day and seem to love it. The other lego lives upstairs in their rooms but the duplo train set now lives in the sitting room to give easy access.
Whilst the deluxe set isn't cheap there is a lot in it. There is enough track to make decent circuits and an excellent bridge. Though I did buy one of the Accessory Sets Lego 10506 Duplo - Train Accessory Set
when i bought this set and I have just bought two more to give the boys the ability to build bigger tracks.
The engine itself is very study and seems to cope with being dropped bashed etc. With wooden railways one of the problems is that the engines never seem to be powerful enough to climb up slopes so using bridges was always problematic. This lego set has grooves in the rails and then teeth on the train wheels so it actually grips. This means it whizzs up bridges and slopes with no problem at all. The engine makes noises as it goes round and also when you put a hose in to "fill it up with water".
The set takes 3 AA batteries and i have been pleasantly surprised by how long these work. I think this is because the engine seems to switch itself off after a certain period. Whilst this could have been annoying it just means pressing the big button on the engine and it will restart. It also means that you don't find that the engine has been going round the track whilst the children have been ignoring it for 3 hours.
The other bits in the box are great. The boys love the crane and the other trucks.
My only gripe isn't really with this set, it's that you can't seem to buy additional bits for it (beyond the accessory kit). To buy another train I think you have to buy the my first railway set LEGO Duplo 10507 My First Train Set
so you can't buy standalone trains and you also can't seem to buy bridges etc.