I'll see if I can find an old disc to test shifting old uploads, but I suspect all the discs I have were manipulated using the same OS and SS4.3U installation.
With respects to the MZ-RH1 and MZ-M200, I haven't been able to find and functional differences, and I'm sure the firmware on both my units are the same.
As I figure, the only difference between the two is that the M200 is geared towards fielding recording and as such, you her the stereo mic w/ extension cable, blank disc and additional ferrite cores.