Originally Posted by Farael

From how I see it, Sauron would have never wanted another Dark Lord, just as bad as him but not himself... because, in contrast with Gandalf or any other of the "good guys" his goals were not altruistic. He was not fighting a war for the pervalence of evil over good for evil's sake, he was fighting a war for HIS OWN dominance over the rest. Sauron wanted Sauron to be the Dark Lord, he didn't want just "a" dark lord.

So, even if the utlimate effect would have been the same (there would be a dark lord who would rule Middle Earth) Sauron would have much rather been that dark lord himself, anyone else (save perhaps Melkor, who is sort of out of the picture) would not have been the same for him.

And even though Manwe brings up an interesting quote, I agree with Rayonor here. Sauron would not have contemplated destroying the Ring because it was not Sauron's nature on the other hand, people of the likes of Frodo, or Isildur or Gollum himself had other motivations and yet they could not destroy, harm or get rid of the ring. In a way, they were becoming more like Sauron and this is what the ring's "corruption" was. It would turn anyone else into a Saruon-clone. Sauron is Sauron himself, so he cannot become more Sauron-like, thus he can't be corrupted by the ring.

Having said that, I want to stress, refering to my previous point, that a Sauron-clone Dark Lord is not what Sauron himself wanted, because his motives were not altruistic but rather individualist.