I needed a scratching post for two cats that I was keeping in a spare bathroom while they were being treated for an upper respiratory infection.  The cat tree had to be small enough to fit next to the toilet and include a place for them to sleep as well as scratch.  Well, I received it and it is perfection.  They love it and use it all the time and what is even better is the fact that after they are recovered I can move it into a spare bedroom where the size and height of this cat perch is exactly right to place under the window.

Pros: Already assembled, sturdy, great size for small spaces, amazingly low price
Cons: I can't think of any