Yeah, I know. I bought that 1928 in "a fit of passion," after the 1986 ban. Thinking about it after the purchase, I figured I'd paid too much. Full auto prices didn't go anywhere for years, and I started to get concerned about having a Class III weapon if they decided to really restrict "normal" guns. Had the Thompson advertised for maybe three years, and then a dealer approached me with a buyer. It seemed like a halfway decent price at the time.
I still wonder, though: what happened to cause Class III guns to take off after languishing for so long?