Instant hit!  We weren't sure our kitty was going to take to this tower like her old one.  We bought this one out of necessity, because her old tower was falling apart.  Within the first minute, after assembly, she was climbing all over this one to explore.  Her favorite new napping place is the hammock below.
Assembly was easy, and the tower is sturdy for what it is.  We took off the little ladder, because our kitty avoided it and it just appeared to be in her way.