The Firefly's seem like they make more sense as turn signals than the Lumos helmet lights.
But the idea of 4 lights plus remote that ALL need charging is just anathema to me.
Lumos is great for visibility but I didnt buy into their turn signal implementation on my Ultra helmet:
1)it only works for cars trailing you and the vast majority of my close calls have been from the other 3 directions.
2) the remote lost charge just sitting in my garage for a few days the first several times I tried to use it.
3) I still have to use hand signals because of #1 plus in my state the law specifies hand signals for cyclists so even if I had confidence in the signals they likely wouldn't count legally as signalling if it were to end up in court.
This Giro seems to address some of the Lumos' limitations but I'm still leary about the signals being recognized by drivers let alone the court should something come up.