I have two cats, one midsize, the other a little larger.  The smaller loves to get up on the top bed, the other goes on the larger platform.  Neither have been in the hammock or basket.  It was very easy to put together and is sturdy.  The only drawback is the configuration of the third platform.  It's not easy for a cat to get onto from the second platform and if I didn't have it sitting next to a window where they use the sill to jump from, I don't know if they'd use it at all.  The steps have never been used, but are cute.  The love the scratching posts.