Not so far. The scientists at the Roslin Institute, who pioneered this work, have repeatedly found that the clone foetuses grow much larger than normal ones, and there is a much higher chance of the pregnancy failing, of stillbirth, or of forced Caesarean sections. Dolly was the one successful pregnancy of more than 277 embryos. Only if you're a woman and use one of your own eggs. So men can't be cloned exactly, unless they get an egg from an immediate female relative.
Scientists think it plays a key role in aging.
A number of theories of aging hold that when the mitochondria run down, the cell dies. Cell DNA damage often leads to cancer - so human clones might be liable to severe illness. But at some stage during its growth, while still in the womb, the cells lose that ability because some genetic switches are flipped off or on. They become any one of the multitude of specialised body cells, and won't revert. That's convenient - it means when you cut yourself, you don't get a baby growing over the cut, you get skin.