We would have rated this cat tree a 5 if it weren't for the fact that it is sometimes difficult for the cats to jump up unto the smaller ledges near the bottom.  Otherwise, they have a great time on it.  I have it set right by the widow where they can watch the birds.
Putting it together was fairly easy, I like the color and texture of the carpet. It's pretty sturdy for my two cats.  I would recommend this cat tree friends.