I use autosol to buff my razors I restored. It works fantastic, supposed to leave an invisible film that protects from rust, but I never really count on it.

I'd worry more about buffing wheels / dremel you're using for damaging the edge. I stay far away from the edge when lightly buffing stains out of my shave-ready razors.

I haven't used flitz, but maas works quite well too. Though I think autosol is abit faster than maas.