As you needs certain level of "graininess" and agent to polish off metal.
I used to use the OEM cloth or Selvyt to wipe my PAM clean. I hesitate using micro-fiber as it might traps micro-dirts, since it has bigger fiber weaving. But then again all cloth will trap micro dirts.
Some recommend using soft lambskin chamois to polish... tried it and it works excellent, I think it's the best way to go. Got mine from a friend who bought it from a watchstore shop in China.