I can't imagine that it gives any more visibility than a high-powered white LED does in the daytime. FWIW, I run a Cree R2 on my helmet during the day in strobe mode and it's extremely visible to both cars and pedestrians. It cost a lot less than the DiNotte and also can be used at night. I wouldn't ride without it, but I also don't think changing the color would make a whole lot of difference. Just my real world experience. I'm sure someone will soon chime in with some sort of study that says amber lights are better because of XYZ....