Practically all the hikers I ever asked said the red LED was a complete waste of money and a useless feature on a headlamp.
Then, on my 100 mi. section in Maine this fall. I spent a night at a shelter with 6 others who all had and used the red feature on their headlamps.
It was the most pleasant, polite night I ever spent at a shelter. All involved were avid, experienced hikers who understood the value of not annoying those around them. We all knew about getting blinded by those bright white lights.
I say be courteous and USE THAT RED LED!!!