Comment by progne

This technology doesn't seem to be limited to existing limbs and organs. After replacing a missing arm you could add a third arm. A man could grow a uterus since he has the X chromosomes and with a transplant that includes Y chromosomes, a woman could grow testes. Parthenogenesis could become a choice. Another head seems possible. The limits are more likely to come from regulation than a reluctance of people to transform themselves.