Overall, I am happy with this product so far (though longevity remains to be seen). However, the particle board that makes up every panel is not as sturdy as I would have hoped. I had one corner completely break off while building the wheel; superglue seems to be holding it together. On several panels, bits of the black exterior chipped away at the edges where the panel locked into other panels. Also, know that it is not as “silent” as they make it out to be. It is not unpleasantly loud, but it certainly makes a bit of noise whenever the wheel is turning.