I recall seeing both a playable TG-16 kiosk, and a display only demonstration unit. The demonstration unit I was was probably the one shown in this thread. I recall seeing it at Children's Palace. I recall that video game section at Children's Palace. Either that same day, or another day, I was browsing the video game tickets at that store and a man shopping in the store was browsing the NES games, he asked if I had played Iron Sword and if it was a good game. H was getting a gift for some family member. I said, "Yeah, I actually have it at home. I like it". And so on. The guy bought the game.
The playable kiosk I recall from Toys-R-Us. It was a playable Duo. It had a selection of games on it, I'm pretty sure it was just running the Gate of Thunder 3-in-1 CD.