The problems are many and severe. Dealers are also prohibited from selling more than one gun at a time to any customer. The remainder of the guns can only be collected after 14 days. Incredibly, dealers are not even permitted to sell common products. But with a bias like that written right into the language, few will have the courage to challenge the implication.
Federal law is ambiguous, and it conflicts with a myriad of state and city laws.
It requires electronics that can break or lose power. It renders a gun useless if one's hands are dirty or the gun itself is dirty. It also makes it impossible for a friend to use the gun in self-defense against violent criminals. Such technology has limited use at best, and then mostly with law enforcement. This technology is also expensive.