My cat Pumpkin was on the tower about 20 seconds after finishing putting it together!  
The quality seems good (although will soon be put to the test), but some of the supports aren't all finished to a perfect standard, but as they're to be scratched at, it isn't something to be concerned about. The platforms and covered boxes are really soft so I think my boys will love to sleep on the tree.  
Was easy enough to put the tower together, I managed to do it on my hour lunch break.  A few times I wasn't sure which holes to use for the inner supports on the two covered boxes (They go in the outer holes so the outer supports are in a line) but having the listing open from my order confirmation email helped guide me along with the instructions.  Thank you, Wayfair!