We have three adult cats.  All three enjoy this tree.  One of our cats is over 20 pounds, he has not ventured higher than the middle center perch, but he fits perfectly on it to do some bird watching.  I'm not positive the top perches would hold our big cat and I have a feeling he thinks the same.  He has shown no interest in the condo part, but I don't think he would fit.  The other cats are both about 9-10 pounds and go to the highest level.  One has also taken to sleeping in the condo.  We placed the tree on carpeting so we did need to screw it down to the floor to steady it.  I think if it was on a hardwood floor and in the corner against a wall it would be a little less wobbly.  I'm overall happy with this because all three of our cats can use it, it was easy to assemble, and looks nice.