You are right. Right after my post, I thought to myself, why don't I call AJ? I did that just now. Had a a very nice talk with him. He answered a lot of my questions for me, that gives more assurance about Ketron products. I sure like Ketron sounds when it comes to orchestra/acoustic instruments.

AJ confirmed for me that indeed the SD7, SD40, and other high end Ketron models have the same vocalizer engine.