Bruce Collins has posted a few interesting details to his Mission Harp Amps website. He has changed the name slightly to the Mission Chicago 32-20 amp. As far as I know there are no changes in the design or features or sound.
One detail he added concerned the output transformers used in the amp: "Custom made, oversized windings and vintage style open frame, paper bobbin." These are the same killer OTs he's used since the amp was first offered for sale.
Bruce recently shipped a Chicago amp with 5881 power tubes that produced 41 watts in fixed bias mode. Crikey! It retained all the warm tonal qualities of the 6L6 amps, but with more bark and punch. What a beast...
Update: My bad... The tubes Bruce used in the 32-20 amp to get 41 watts were 6L6WXT+ tubes. You can order the Chicago 32-20 amp with these tubes, no extra cost.