I'll give my opinion:
- Orson Welles: though he is the least attractive Rochester, I thought he was excellent. He looks decidedly unconventional and radiates a kind of brutish sexuality- the kind of thing that Jane hates by principle. If we're seeing things through Jane's eyes, his coarseness may well be magnified. It's much easier to see why Jane would be repelled and conflicted by this man.
- Timothy Dalton: certainly the dreamiest Rochester for those who like him as a romantic hero. In some respects I think he's too nice but he conveys passion very nicely. He's clearly far from not being handsome but Jane wouldn't fall for conventional beauty. As played here, I think it's meant to be surprising that she doesn't fancy him.
- William Hurt: he looks gruff and weary, clearly a man with history. I think he does bring something to the role; here Rochester looks like a man who's on his last legs and sees Jane as his only chance of redemption. His need for Jane, beyond love, is apparant.
- Toby Stephens: again, going for a softer approach like Dalton. Convincingly less attractive so we don't end up shouting at the screen in the way we do with Dalton. His performance is quite faithful on a surface level but I think Rochester should be more of a loose gun.
- Michael Fassbender: I thought he was all right. Yet again, it is a more diluted costume drama approach where Rochester appears grumpy rather than tortured. More Austen than Eyre me thinks.
So I believe the performances fall into two camps; Rochester as a Darcy-esque romantic hero and Rochester as a psychological wreck of a man. Although I don't mind either interpretation, I think the latter is closer to the book and would like to see more versions of that.