I found the sd-2300 by searching my local Craigslist for sd-2300. The ad had been up for about a month so I figured I would give it a shot. It turned out he still had it so I made a day trip out of it with a friend. We drove about 160 miles round trip and unbeknownst to me, the person selling it had a copy of Next Tetris included with it's documentation! My heart about jumped out of my chest since it is a pretty rare game.. pretty happy with it.
What I am getting at isn't so much about the unit it's self but rather that copy of The Next Tetris which was a mail away freebie for that specific Nuon player. That makes it one of the rarest Nuon games and the by far the rarest officially licensed version of Tetris out there.
I'm on a page about incorrect corrections, and spent the better part of like two hours trying to get someone to understand that -5^2 = -25, not 25, and then that post had comments get reposted because that group is self sustaining, and that person was in turn trying to explain what I just explained to them. And I'm taking that as a victory