It's unique for several reasons - the early ones varied quite a lot as you know, with different pickup spacings, pickup types and construction. This is one of the earliest with the now traditional double near the bridge configuration and is unusual in that the bass has a dark bookmatched top. The BT shape remains to my mind the classic Smith design.
As said above, I firmly believe such a great example of such a pivotal bass will grow in value over time, especially as Ken is changing his business setup and, although things have always been outsourced to some extent, I don't know what'll happen when Ken retires.
So I'm in no rush to sell, and quite happy to keep it but if another player wants a unique piece of history and a thoroughly modern and fantastically constructed and sounding bass for less than a new one - let me know