Hi Gary,
I've never made experience with the Kamui black SS, but with all other medium and soft Kamuis that I used or installed to others there was very high consistency during the period of use. But if one asks my advice for a well playing medium multilayered tip, I first tell Moori medium. It is the one tip that is very similar from tip to tip, and this is worse at the Kamuis. What is difficult to separate is that there existed (or are still existing) some fakes from Kamui. I also had two of them, and they were black medium, but hard as a stone!
Going back to the original question, I think one must know, that most tips are the more consistent the harder they are from the beginning. And if it is going about soft qualities, the multi layered tips are usually more consistent than single layered with kess mushrooming. But I don't know one tip in soft quality, that is consistent from the beginning to the end and does not mushroom. Even not a soft pressed milkdud.
It would be interesting to know about the situation of fakes. Are there still fakes of Kamui or also from other brands?