I agree that the Moog EP-3 is a good choice. I have one, and it works well with my P6. I also have a Yamaha FC7, which does not work so well with my P6. The range of expression, min to max, on the FC7 occurs in the first half of the pedal movement (e.g., not very expressive). I think I read on this forum some where why that is, but I can’t remember now. The FC7 does work well with a different keyboard.