Unlike the Tuff Balls, these were decidedly short-lived. Within five minutes or so, Elka had cracked the rubber and was shredding the plastic off of one, a practice I discourage each time I see, but doesn't seem to stick.
So, I took it away and gave her the next one. That one, I'd say, she took a thoughtful ten to fifteen minutes with, and made me a work of art, which I will now share with you.
While they may feel rather sturdy and solid if one were to squeeze a ball in your hand, one must remember that these are but human hands, and not Doberman jaws. I will tell you that I cheaped out and did not get the Zoink! Extreme balls (I was in Price Chopper, not shopping via Amazon, and that will frequently make the dog toy price difference), and perhaps that was my mistake.