My dad used to build "puzzles" like this when I was a kid; I don't remember any of them being quite this fancy and deluxe though! Love the different shading, the contrast between the bare wood and the charcoal wood makes it not only look classy, but makes it easier to see all the intricate levels that your marbles run through! There's a really nice variety of slides & chutes & spirals to watch your marbles do, too, it's really cool.Building it is definitely complicated, but they have made it as clear & as helpful as possible! They include all the helpful tools you'll need, including a small wax stick that you will need OFTEN (though I will say a small emery board is far more effective than the little square of sandpaper that these things always include). It can be quite a challenge to pop out some of the pieces from the wood sheets; I recommend a very thin scalpel to cut the connections before attempting to push them out! I did wind up breaking a few pieces but they glue back together easily.Only complaint on this is that some of the pieces are a little warped. That always seems to be the case with these kits, but I don't usually worry about it because the issue usually straightens itself out once the pieces are all snapped together properly. Unfortunately, I should have worried about it more this time, because there are things you can do to mitigate the warping before assembly, and now it's too late! One of the very large, semi-circular pieces that keeps the marbles lined up as they go into the chute was bent, and while assembly helped, it didn't help enough, so now approximately every 1 in 12 marbles jumps out & goes rolling across the room. It's still cool to see the other 11 marbles.Bottom line is, it's really cool, fascinating to build, looks great when done, but if you notice a piece is warped, deal with it before you begin assemby.