I draw the lines at enslaving full human clones, lobotomizing them, or denying them human rights. Deliberately creating anencephalic clones for spare parts is fine. Creating chimaeras or hybrid clones is ok, I guess, but weird. In most cases there's no real point to that. Do we really want to create a race of mermen who can breathe through gills? Why? We have robots who don't need to breathe at all and don't demand rights or paychecks (yet). Other than that I'd be fine with cloning if only the techniques were more efficient. 4000 failures to one clone does not seem like a mature process to me. And we don't really need more people on this planet, so it's doubly inefficient.