This is a fantastic set. It is easy to build and only takes a couple of hours to put together. It will look great under the tree, but you will probably have to buy more tracks. I bought the additional Power Function parts to motorize the train, because, well, TRAIN. (BTW the automation is not required, and pushing the train is just as fun as using the remote.)
MODS: Like others who reviewed this set, I found the engine car too light to carry the motor, and experienced slipping of the wheels, especially when I added another car. I took another reviewer's advice and moved the motor to the tender/coal car and moved it to the middle of the train. It then worked perfectly. I also thought the smoke was a little small for the train, so I made that bigger. Like others, I found that the lamps on the last car made putting a full sized minifig on the outside of the car impossible. I compromised by taking the lamp off of the roof and putting it on a gold pole I had in my stock and had the ticket-taker hold this pole/lamp.
MORE MODS: After all this, I watched the Polar Express and decided to turn my new train into the Polar Express. I added a couple of kids and put the hobo on top of the additional car, which I made into the toy transport car for the movie. This ended up being a great place to put the toys that you make in the set. I added an area at the front of the train to stand and made the lamp on the engine bigger.
This is a super-cool set and I had a blast making all the mods for it. I think it will be a great addition to the North Pole Workshop and Winter Toy Shop.