it depends on how it's used.
if it's used to make organ farms out of living beings, then no. that's hardly ethical. practical, yes, but there's absolutely 0 ethics involved in that sort of practise.
if it's refined enough to clone endangered species, or to clone things like plants for food, that's rather ethical, i'd suppose. there's probably a large debate behind it being 'natural' or not, but it's ethical if it's going to be beneficial to a species and the world.
what matters, at least to me, with cloning, is whether or not those that practise it are going to realise that the things they clone will have feelings of their own. skimming over whether or not they have souls (or whether or not souls even exist), they will feel pain. they will feel physical, mental, and emotional pain. they will have their own thoughts (if human) and actions, and will be very, very real and very, very alive.
i feel if cloning human beings does come into play in order to have a living breathing plant for organs/limbs, they should know. they should have the right to be judged as a human being and have a choice to refuse to be used like that. they should have a chance at actually living and not just be cooped up in a pod matrix-style.
though, if they were able to clone human beings but have the brain snip-snipped enough that they cannot feel or think, the line blurs and i find that much more okay of a deal to have an 'organ farm'. but it does make me a little squicked out to imagine screwing with a living thing's brain like that and turning them into a literal vegetable used only for harvest.
shrugs! i don't think we're quite close enough to having to worry about this sort of thing. it's still a very imperfect process and concept.