The bad: in models/versons past, the dark brown cubes were made of durable felt.  But this teal version is made of super thin nylon that is already ripping and shredding 2 hours out of the box. Furthermore, the top tubed seams that the plastic rods go through are simply velcroed shut and a 6lb kitten sitting on top of the cube has already managed to exert enough pressure that the velcro is coming undone = the cube is falling down bcs the sides are coming off the frame.  The dark brown felt was completely sown across the board, so it was impossible to come off the frame unless it was cut with scissors or the tube was removed and the fabric slid off the tube.  This is a shoddy version of what I considered to be one of the best things I could ever buy in my 18 years of fostering kittens. The frames are still great, the modular design is sturdy and customizable.  But, the construction of the cubes and tunnels....nah NOT WORTH THE PRICE