If it were someone I knew I would use the color. If I were more interested in the photo for the photos sake then I would use the B&W.
B&W is not kind to her skin but it make a powerful photo.
I'd go for the colour shot myself. The B&W shot makes her skin look really aged. I noticed that the two shots shown here were not exactly the same perspective.
Many thanks for your opinions. This will be used in my "in progress" piano people book so I still have many many days to change my mind. So now I just wonder if I should try the B&W with the same crop as the color one...