Possibly the lack of interest comes from perhaps the idea that most of the arranger players that DO care much about tweaking their styles and registrations live have already got an arranger with the sliders built in?

You might also consider that probably 90% of all user arranger demos I've heard has the RH voices WAY too loud. Perhaps not as many as might be expected can even tell the difference between a well mixed style or registration and one not so balanced? LOL

BTW, if you switch from the preset for volume to the preset for reverb (or anything else you might have up) do you have to reload the Registration to get the faders to jump to their active points?

BTW, I have a BCF2000 myself, and have used it to control my DAW on and off, but must confess, as well laid out as the G70's sliders are, I have never been tempted to use it for that...