As the one who started this thread, I’ve pretty much given up on this idea, for several reasons.
1. As well as being the bass player, I’m now also the unofficial lighting engineer in our band, so I always make sure there’s a spot pointing in my direction:)
2. Seems that any passive luminous material has a limited life of maybe 10-12 years. I have some basses that are nearly 40 years old…not that I would drill one of those, but if I did fit Luminlay I’d expect it to last the life of the instrument.
3. I’ve had reasonable success with simple luminous spot stickers bought on Amazon. If you carefully clean the oils off the neck first, they’ll last several months and are easy to replace. If I know I’m going to playing in a dark hole, I use a bass with those on.
I do find the FretFX approach interesting and might consider that in the future, although if they shine brightly towards the front/audience then personally that’s a no-no, as guitars with bright LEDs look pretentious and stupid in my humble opinion.