Really cool to see how quickly the PFM2 can switch/load patches. Currently using this for percussive sounds to get the most out of the four timbres on the Preen while using an external sequencer. For instance, if you have a MIDI track open in Ableton, and you automate the program change to alternate between 'kick' and 'snare' (or any synth sound you want) on the same track it works very well, even at 300 bpm!
Two very crucial tradeoffs to consider if you're using this method tho:
1. Your voices will be cut short on every channel, even if you're only changing the patch on one of the channels. If you're planning on doing this, make sure that any sound you want will only last the length of the shortest point between patch changes. Best to stay clear of pads.
2. Make sure that your sounds are all dialed in before you start doing this. Any unsaved changes will be lost when it switches programs, and DO NOT TRY TO SAVE A PATCH WHILE THE SEQUENCE IS PLAYING. Not sure what happened exactly, but the patch saved in two separate locations in the same bank when I tried. Losing a patch is a small price to pay for the reward of experimentation though, so this method is still highly recommended.
Figured I'd share this in case anyone hadn't tried it before. Loving this little guy more every day