Got it today!  I put it together in under 15 minutes even with the cats diving in and out of the box.  Seems very sturdy and both cats love it.  Very nice size, not too intrusive but great height for the cats.  I had a cat pole that went to the ceiling before and this new tower, the highest perching shelf, is just as high as that one.  This one seems sturdier and looks a lot nicer, very happy with this choice.