Cloning will increase social inequalities, because only the richest will be able to afford it. An excellent argument. Differential use of NRTs could increase existing differences between classes in health and longevity. The only way to prevent this is a universal health care system guaranteeing equal access to even the most expensive NRTs and restricting their use to infertility that cannot be treated otherwise. Cloning is unsuccessful.
Cloning is unsafe.
Cloning will produce damaged children, because the cells of an adult human have been exposed to environmental toxins for many years and have developed new mutations. Animal experiments are necessary to answer these questions. It would be unethical to proceed with human cloning until animal experiments have proved its safety. Cloning is a denial of death. So is having children in the usual way, at least in some cultures.