Unless something has changed, Streamlights have never had a really durable coating. I don't know enough about the differences between Type 2 and Type 3 anodizing. Or for that matter the differences alloys of alluminum that the anodize can bond to better or not as well. I just know a Streamlight with heavy use tends to show a sort of petina after a while where alluminum starts showing through at edges and corners.
Many find that look charming. It's like battle scars.
A SureFire 6P with coating removed.
I bought it like this about a year ago and have not polished it or anything. I use air craft stripper to clean coated alluminum car parts. A plastic putty knife, a dental pick and a toothbrush.
A 4 year daily trouser pocket carry versus a shelf queen.
And remember folks, chicks dig scars……