I performed for the first time with the HDM. Not perfect. Even though I put cheat notes on the device where I had styles stored, it's going to take me a little time to remember well where everything is stored. Also, it occurred to me to put the bank control on the right side of the PSR2000 where there is nothing. The advantage to this is that I can change banks while playing the chords of a song or while scrolling through styles. This will be a wonderful advantage.
It does take a few seconds for the device to change banks once a new bank is selected plus it takes the customary time like a floppy to wait for the CHECKING message before the styles appear on a bank. So there can be downtime while changing banks. But if you change banks while playing a style, and you get to the end of the song, when you access the floppy drive the styles on that bank will appear immediately - completely eliminating downtime -except for the 2-4 seconds to load a style.

I am happy to say that my floppy days are over - at least for live performance.
Beakybird