We try to keep our purchases of commercial dog food products at a minimum in favor of our own food products, since quality is suspect in any commercial dog food product, regardless of what they say about the product.
For chewing, we try to stick with raw meaty knuckle bones that are large enough for our dogs to not be able to wrap their jaws around, which can increase risk of teeth fracturing. We also use interactive Kong-style toys stuffed and frozen with our Peak power Snack Stuffer.
But for more variety, we purchases these bully sticks, which work well for our dogs. Depending on how heavy duty of a chewer your dog is, these could last fifteen minutes or an hour.