Oh I'm of the opinion that cloning will lead to trying to create a "perfect human" not in the sense of "Master race" but along the lines of eliminating every mutant or faulty gene that causes illness or disease in the clones.
Personally I'm not against that, a new humanity that has dominant genes that prevent inherited diseases would probably be a plus.
The thing gets messy when we start talking about the duplications of sequences that currently exist in our genome that causes problems. If the backups are eliminated and we drop from 20000 some genes down to 10000 some genes have we in effect become Rossums Universal Robots.
"Ah now, young Rossum; that was the start of a new age. After the age of research came the age of production. He took a good look at the human body and he saw straight away that it was much too complicated, any good engineer would design it much more simply. So he began to re-design the whole anatomy, seeing what he could leave out or simplify. "http://ebooks.adelaide.edu.au/c/capek/karel/rur/
While all that is a matter of if and what the real problem is legal issues not scientific or moral ones. Already we have companies copywriting patenting and trademarking genes, imagine what happens when a Monsanto type owns most of the cloning tech. I don't worry about a world full of clones, clones aren't their templates, they are born just like everybody else and have tolearn just like everybody else. A clone teenager will have the same perks and flaws of a real one because s/he is one. The obvious reason for cloning will be some rich big wig who has no legal heirs to have one to inherit the fortune when s/he dies. The biggest reason will be cloned bodyparts, but hopefully not a whole body to harvest parts from.
To me cloning is more of a fearmongering issue than a real issue. as I said the success rate is terrible, so its a long way off at best before it becomes a real issue.