This is my cat's safety place, her fun place, and the place where she observes the world both inside and outside the house (I put it next to a window).It is sturdy and was not a problem at all to assemble.  I have kept the ratchet tightener that came with it because in my cat's enthusiastic climbing it becomes a tad loose every now and then, but tightening fixes that right up! 

Pros: Neutral color, easy to assemble
Cons: needs vacuuming - if only I had gotten a color to match the cat!  ;)