I have the foot pedals. I never use them, because it is so convenient and comfortable to hit Ctrl/Alt with my thumbs. Maybe there are better keys to assign to my foot pedals, but I haven't really thought about it much.

I recently broke my arm and have been using foot pedals. I grabbed generic ones, and they help. I can't speak to the kinesis ones, they didn't seem to be easily programmable. The feel of the pedals I bought is horrible. Screwing them into a board with a carpet pad beneath helps a lot for organization.

I have a triple foot pedal (from an old dictaphone) but never use it.