Nothing is ever perfectly black and white. Even in an organization as evil as the SS, there were certainly some people who were good. There is at least one well known story of a young SS officer saving Jews and helping them to escape.

EDIT: Probably much more common were people who were complex like Kurt Gerstein. He was an SS officer charged with overseeing hygiene and, as such, witnessed murder in the camps. He claims to have tried to inform people about the issue and to have secretly dumped shipments of zyklon B, but did not (or could not) do more and there is little evidence of what he did. So was he good? Less evil than others? Or just telling stories after the fact to avoid punishment? It's complicated and impossible to really tell given that he would have had to be secretive.