Have you considered a Buddy Belt Harness? I would think with the design and the proper fit it would be nearly impossible to chew. The harness's buckle sits between the shoulder blades and it has an "O" ring to attach a leash and tags. The harness is also designed to eliminates strain on your dog's neck and spine, helping to prevent damage to the throat and trachea. Yazmin has never chewed collars or harnesses but she pulled a lot, causing herself to choke and cough while walking. Since wearing a BB, she's not had that problem once!
If Prada's still growing you may also want to consider the BB2, they're less expensive but still have the same quality and design as the original Buddy Belt.
Buddy Belt Harness