If one has front and rear lights, and if one pays attention to batteries and the like, then I don't see the value of adding reflectors on top of that. Marginal risk reduction near zero. More of a factor is that dangerous drivers don't look or think, not that they look and think and STILL miss you. Now, hopefully, no one bought a camo bike jersey - yes, they actually exist. "Phone call for you, Dr. Charles Darwin calling."