Put me down in the "neither" camp. Both are incredibly flawed versions of Superman. If I had to pick one, I'd pick Returns because of nostalgia and at least he didn't kill anybody. But that's a low bar. I don't consider Returns to be part of the Donner-verse. It's a stand alone thing and that's fine. Supposedly if Returns had gotten a sequel, we'd have gotten Brainiac as the main villain so I'm sorry that didn't happen but supposedly that's what we would have gotten with the sequel to MOS too.