Don, Some purists prefer the “tin sandwich” of the Marine Band, because it has the “Hohner Sound” that is unmistakable. However some folks have a skin reaction when their lips touch the brass reed plates and the old nickel plated cover plates. These players prefer the Special 20 comb where the reed plates are recessed in the comb.
My preference is the the Hohner Rocket. It and the Special 20 are both in Hohner’s “Progressive” lineup and I have never been more happy with a harmonica than I am with my Rockets.
Be careful Don… you said that you are warming up to the Special 20. I can assure you that when you try a Rocket, you’ll never look back at any others.