It is very nice but the top part that screws in does not screw in tight enough.  It is very wobbly and when my one cat climbs up there it looks like its going to break.  My other cat will not use the top level because its not stable.  It has been like this since day one but I did not want to take it all apart and re-box it in order to send it back so I kept it as is.  I have tried various fixes with no luck