When I did TZD's upgrade offer in 1996 or so, the Duo i received was shrinkwrapped, had the band around it about the free games inside, and my free Hu-card was Splatterhouse. I already owned Spaltterhouse, so I left it shrinkwrapped, and I think it's still sitting inside my Duo box.
The trade-in program, I forget the exact details concerning that. I know I had to trade in a fully functioning Turbo Grafx 16, with all the hook-ups (RF, AC, and 1 controller). I pay shipping for the Grafx going to them, and the Duo coming to me, and sent them $50, maybe $100, I'm pretty sure the total, plus all the shipping, was under $200. In exchange they sent me a Duo.
I recall asking the guy at TZD what they did with the Turbo Grafx systems they received in exchange. I think he said they were then donated to orphanages, or something similar. Tax write-off stuff I guess.
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