"Cinnamon, our pit bull mix mutt, destroys toys. And sprinkler heads, and rubber garden shoes, and the Zoom Groom we got for giving her scrubs at bathtime. In fact, I can confidently leave *out* the object and just say "she destroys." Anything she can get her paws on. I'll be playing with her, I'll sit down to do something, and half an hour later I'll realize I left her chewing on the Good Cuz / Tuffie / (insert toy of choice here)... and I look over and the Cuz is missing a foot, or the seams are gone on the "SUPER TUFF" ballistic nylon toy and there's stuffing everywhere.
So far we've had zero problems with our black Extreme Kong toys. The red ones, which we bought in mid-May when we first brought Cinnamon home, are beginning to show signs of wear; the black ones are still dent-free after more than a month of chewing. I can confidently leave her to gnaw on these for as long as she'd like, and I know I won't find little fragments of rubber sprinkled on her bed. Plus, of course, there's the fabulous "lick-it-out" aspect; I crush some dry treats, mix them with peanut butter, and I know she'll be kept occupied for a while... long enough for me to go grocery shopping or run a few errands. She absolutely LOVES her Kong toys."