I don't own a 9100 (to my most sincere regrets), so I have to find the answer to my curiosity here: In pictures of the 9100, it often seems to me that the plate right to the display with the lettering "x-keyboard, y -accumulator, z-temporary" is backlit. Is this true or just due to the photographs? I have a 9810 with the same lettering, and it's definitely not backlit.
Just for curiosity -
Andreas
(and if yes, what about the model B, would be the next question)