Yamaha DTXpress/DTXplorer/DTXtreme

Hello everybody,
This is a fantastic group! I am a new member, and I will be receiving
my DTXpressII In January. I can't wait!! But, I just had a quick
question: is it possible to attach a pedal to the DTX that will allow
you to switch between presets? I have heard rumors about such a pedal
with 3 switches: up through the presets, down through the presets, and
select. Does anyone use such a thing? Does it even exist? It seems
like it would be pretty difficult to hit those tiny buttons on the
brain while jamming to change kits.

Thanks in advance,
j