I've gradually gone over to the "non-flashing at night" point of view. I have a Dinotte 300r tail light which is incredibly bright. Now when I use it as a back-up, I keep it in non-flashing mode and on one of the lower brightness settings... still pretty bright. My "back-up" headlight is a Light & Motion "Seca 800", which is quite bright as well. It has a beam pattern more suited to trail riding, so I keep it pointed down so as not to blind oncoming traffic.