What I love most about this cat tree is how great it looks, because it doesn't look like a typical, ugly carpet covered cat tree.  I have a modern look to my condo and the curved wood of this tree makes it look like a sculpture when my 2 cats aren't on it.  When my 2 cats are on it they love playing and lounging on the different levels and one of my cats enjoys hiding in the little cubby hole on the bottom level.  I would recommend using the included stabilizing piece as it can wobble a bit, but it remains sturdy overall.  I think the way that the main piece is curved causes it to be a little wobbly, but not to the point that there is a danger of it tipping over.  On the negative side there is some difficulty in getting all the holes to line up when assembling it.  I found that the trick is to tighten them all gradually so that there is room for holes to line up properly.