My 75B had the black heat treatment when I got it. I polished all the visible portions with the slide closed: bbl tip, all around the ejector port and some more. NICE and shiny and never corroded, but was shot regularly and never a safe queen. A fling with bling.
My 75 Shadow bbl was also/is all shiny metal with the ramp and areas visible through the ejection port sections very polished.