I live about 10 miles from 3M outside of St. Paul. I also work with the 3M cam center from time to time on finishing projects for the metal industries (mirror stainless, medical device etc) I will ask about this when on the next invite I get there. I buy 6 figures of product, so they treat me well and give all kinds of test stuff. Infact it can get annoying once in awhile. If anyone remebers, I had a post where I used a 7" brown scotchbrite to strip paint on an entire car. Sounds nuts, but finish was right where it needed to be for a quick DA and prime and it was fast. Heat was almost non existent. Freebies from 3M. Like I said, I will ask around.
P.S. I know they have product down to 4 micron=mirror