I'm chiming in too, because this is a great question/one I've also wondered about. I'll definitely be adding bestbullysticks.com to my online favorites list! I have another question though. Are pizzle twists and bully sticks similar? I bought Chica her first ever pizzle twist at Petsmart last week, and she had it gone in literally 10 minutes! She is a very aggressive chewer, more so even than our yorkie-poo who is quite the chewer himself! I also got Chica an antler at petsmart, and she likes it well enough (especially after I "marinated" it in an empty bacon bits bag), but I've heard Ziwipeak antlers are better/a little softer, so I plan to check those out as well.