Just put in a W3Z2 today..
I went from the original 95' DZA1 F5LF-12A650-AB to the 93' W3Z2 F3LF-12A650-AC computer, don't really notice that much of a difference, I haven't been able to really test it out, I just took it for a few mile cruise on side streets so I couldn't really open it up much, it seems like it's little more responsive, but the one thing I can tell is improved is how it shifts. Shifts seem more firm and just all around the trans shifts better. Also noticed my traction assist appears to be disabled which is cool, when I hit the traction off button the idiot light doesn't pop up anymore, so I assume it is disabled.
When I get an opportunity on a long stretch of road with nobody around and no cops for sure I will test out the speed limiter theory..