There is one more thing that you might try ... I believe that Sears, as well as the othr major vac makers, have a "dry wall dust" filter that slips over the sponge filter in the vacuum. I have already cleaned up Portland Cement with that filter and none came through. Maybe that would work with...
I would like to add another vote for FLITZ. I think that between FLITZ and Semichrome a person wouldn't need anything else. Also, FLITZ has a polishing ball that mounts in the end of any drill. Go over the wheel once by hand and then hit it with the spinning polishing ball. It works miracles...