I met a couple of nice guys from Morningstar at the NAMM show last month and told them how I'm using the MC6 in my keyboard rig as a remote control for the MPC Live. Due to some deficiencies in the MPC's MIDI sequencer, I have had to program some MMC "macros" in the MC6 to force the sequencer to send bank select and program change messages to the Korg MS2000 synth. For example, to get the MPC to transmit program changes without playing the sequence, the MC6 preset labeled XMIT PC sends four MMC messages in a row: reset, deferred play, stop, reset. The messages are transmitted quickly enough that the first note of the sequence does not sound. This is used when I've changed the sequence on the MPC, the MS2000 has the incorrect patch loaded for the song I'm about to play, and I need to change the MS2000 patch and play the synth before starting the MPC sequence later in the song.
My only complaint is that the MC6 preset editor is rather convoluted for programming system exclusive data. Having to translate from "F0 7F 00 06 44 06 01 00 00 00 00 00 F7" to "11 127 0, 6 68 6, 1 0 0, 0 0 0" is quite tedious. But I haven't seen many people using the MC6 in this way. It does just what I need it to do and I'm looking forward to finding other interesting uses for it.