I find that they do help with night vision. They need to be aimed as the headlight is, and aimed to the high end of the low beam height as per the owners manual (which is a basic guide).
I personally believe that we (motorcycles) should be allowed to have as many lights as possible on the front of these motorcycles and bright as hell! "Oh, I didn't see him/her" would be a tougher time proving. I wish to leave these aux. lights on all of the time! If they are aimed with low beam, they are less obtrusive at high beam than two auto headlights anyhow!
BC
BTW, I installed mine without the turn signals mounted on the brackets. I like the turn signals where they are, on the bars and no lower! These wonderful folks in their automobiles need as much distraction as I can give them for my safety.