Some of the things they give you in the kaiseki dinner are on the menu; many aren't.
Is it worth it? Well, it's fun. But I can't say that it was a much much better experience than ordering off the menu here. Well worth trying -- but let's put it this way: I wouldn't avoid Kyo Ya if you can't have the kaiseki. A regular meal is probably a better value.
That said, this was a parade of exquisite dishes. Some were better than others. But none was less than excellent.
You know what my very favorite piece of food in this long meal was, though? It was the oyster, as described above by Orik, that in the kaiseki came with the sashimi course. I thought it was almost stunning how good it was. So everybody do what Orik says: go there and have the oysters.
i agree with the oyster, it was terrific. completely forgot about the dinner we had earlier this month. great sake list, lots of good stuff by the glass, too. some truly great off-the menu stuff they sent.
the tongue, however, was very dry and flavorless, as was the smoked eel. alas, no shirako the night we went.