It is a big difference DNJ.Harmonies are much smoother and more natural sounding.In chordal mode sometimes it doesn't know what to follow, and it sounds pretty bad.I also avoid to change gander of a harmony voice.That way it sounds the best to me, when it's your own voice.Like I said I wish Yamaha would give us a user scale.But, I believe for Western music it's not a big deal anyway.