And what's the advantage? I'm looking for something that can control the wah effect in particular. I know that you can set your sustain pedal to sustain/rotor to control the Leslie speaker anyway, so I don't need something for that, although it would be nice. I've got a guitar wah-wah, though, so I could just run the clav effect through that if the expression pedal can't do that. I've heard Yamaha's FC-9 is the best quality but requires some kind of polarity change.
