Have to weigh in on the use of them. I've been riding for 48 years, and the two accidents I was in early on were drivers pulling out in front of me at an intersection. I wish modulators were available back then. I remember when people bitched when the Feds made it mandatory to use headlights all the time. "It's terribly, that light shining in my mirror is really a distraction". I've used a headlight modulator on my bikes for at least 20 years and my "perception" reality is that they increase my visibility and therefore my safety.

The riding conditions are becoming increasing dangereous as drivers who no longer give a s#%t about the rules run left turn red lights, ride the shoulder to make a turn right under the sign that prohibits it, make prohibited left turns across traffic to enter a business and ride the restricted median space so they don't have to wait in line to get up to their left turn lane. And I'm supposed to care that they might be bothered by my headlight modulator? Screw that, I'm tired of caring what others think, I am only concerned that I am seen as I approach the intersection or the azhole crossing the double yellow coming the other way to get where they are going a little quicker.

I don't set out to piss people off, and if there is really slow traffic and I am in a stream of cars I will turn it off. But once the flow opens up, and there is opportunity for that texting soccer mom to pull into traffic right ahead of me, it's going back on.

On my other bike that has a HID low beam, I had to use the high beam for the modulator, and yes, that is more of an "irritation" issue. On the F6B, I wired it into the low beams, and the effect is better due to the dual beams and quality of the lighting, with much less impact to the driver ahead of me. I don't run the high beams with the modulator; as I said, I am not out to piss anybody off. But I am not going to give ANYBODY the "I didn't see him" excuse if I can legally do anything about it.