At one time I traveled from West Palm Beach to Orlando for the annual organ concert. They demoed the leading organs, Wersi being number one. Every type of music from classical, jazz, and rock. Before they were using registrations, it was fantastic to watch their hands play and make changes. One performer played the Flight of the Bumble Bee with the bass pedals.
I never thought for one minute that their performance was recorded. As the years past registrations were used, and then recorded backings. Then the organ became something else.
I had a Wersi Delta 500 organ in my home, and a smaller Wersi organ that allowed me to remove the top part and used it as a keyboard.
John C.