I recently bought a JW iSqueak Ball for my three dachshund pups. It seemed to be a pretty strong toy, and I needed something strong for them because they are all chewers. Well, I'm happy to say that this ball has proven to be very sturdy. It makes a squeaky noise which scares one of my dachshunds (he's a timid sort), but the other two love to bite and chew on it.
So far, as hard as they have bitten on it, they have not been able to harm it. Since it is a ball, they can't grap onto anything to rip it. My youngest dachshund loves to squeeze down on it and make noise with it, and he'll chew on it where there is a small hole which allows it to make noise. But try as hard as he can (and believe me, he can try pretty hard), he has not been able to bite anything off of this ball. Eventually he gets tired and walks away, then later he'll come back to it and try again.
I really like the fact that I was able to buy a toy for my dachshunds that has actually lasted. This is a great toy for a dog that likes to play catch and for dogs that are chewers.