First off, this cat tower is beautiful, and both of my cats love it! They are large cats, at 14 pounds each, and they have no problem fitting on any of the levels. In fact, the top level is big enough for them to lay together! The tower wasn't too difficult to put together, and took about an hour. The tower is slightly wobbly, but not so much that I worry about stability or it toppling over.  My only gripe is that the included plastic knobs meant to cover the screws do not stay in place...but that's really only a cosmetic problem. If you are looking for a visually pleasing piece of cat furniture...this is it!