When I was involved in analog audio over fibre back in the early-mid 90's, we mainly used FM to modulate the audio - it was very good, and we could multiplex many channels of audio.
I've also sent audio over fibre in much the same way as the LightLead - it also sounds very good, and if they have fixed lengths and no need to for an AGC, it will be good. Will be at as good as using star-quad or a digital system - no, but it might have colourations that the end user actually likes (much like valve amps).
I've backed the project as I think it has merit, although I think there is a certain amount poetic-license applied to the KS promotional material...