I’ve used an FC7 for Perf up/down before, and I had virtually no problem. And a quick double tap can take you through a ‘center’ performance from one below to one above with the same degree of precision.
Think about it for a second… your right foot executes sustain presses with millisecond accuracy. Your left foot is equally capable, and as long as the switches are tactile enough that you can feel them at all (I used to have a bit of a problem with those ultra cheap plastic tablet style ones… too light to feel, too easy to kick around), you should have no problem.
After all, most organists can work up to two octaves of bass pedals and play intricate lines without looking or clamming. Took a bit of practice, but we’re talking about just three switches and the odd occasional press or two.
Worth a try, if you ask me. Remember, the Performance can also call up layers, effects, Part volumes, mutes, assign switch layouts, d-beam assignments, changes to velocity sensitivity, expression pedal assignments and a host of other things the OTS can’t. You lose so much restricting yourself to just two or three Performances.
You’ll never know until you try, at least! 😎🎹
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An arranger is just a tool. What matters is what you build with it..!