I tried the reverse here with a pic of me mum. So the one on the left was coloured by hand back in the 1940s and the photo I remember looking at as a child. Out of curiosity, I did a quick converted to b/w (& sepia) in photoshop.
Since the hand-coloured version brings back fond memories growing up, it's the one I prefer for this particular photo.
Generally, I prefer sepia - but yeah, it's a personal preference.