I received this kit last year for my birthday, and finally finished it up recently. It is a really nice kit, that requires only a little modification to support it. For instance, I've run support cross bars under the floor as large sections are unsupported as it comes, but that is very easy and does not require precision work. Some balsa or plasticard cross beams and it firms the floor right up.
To give it a bit more flavor I did add some light spackle to the walls and I have added custom wood floors for all of the rooms. Eventually I hope to add some rugs on top as well, but that is a another day.
At any rate, I'd highly recommend the kit. Make a few small tweaks to it, and it works out great.