My cats adjusted quickly to using it. I rated a 4 out of 5 because it does not feel sturdy enough as is. I installed several “L” brackets and angle brackets which made it way more sturdy. It did not fall apart while I moved it. I replaced my 3gallon tank with a 10gallon fish tank (111 lb) on top and it’s holding up well. Shipping was on time and it was delivered safely to my door. The product I received did not have any defects, missing parts, or scratches. The instructions are straight forward so I had no issues building it. I used the styrofoam in the box to cover the right entrance. Overall, I’m satisfied with this purchase.