I've  used it once only because it has been much too hot to take a walk here in TN. It rolled over the rough sidewalks easily, and I was shocked that my thirteen year old fat cat adjusted quickly, and seemed happy and surprised to get outside. I now have an excuse to get my own exercise and stimulate my bored kitty who is strictly an indoor boy.
It took a little effort for this 75 year old to put the wheels on, but I did it! I have no comment yet as to how sturdy it is until I get more use out of it.