When I biked to work and back every day I had one headlight. But I had 2 backlights, 1 reflector and 2 red flashing LED lights attached to my backpack. I figured that my front light was pretty bright and I could see where I was going. I took a lot of care in the dark. And the reason I was lit up like a christmas tree on the back was because I don’t trust car drivers at all. I’d be amazed if any cyclist does. I wanted them to be in no doubt at all that there was something in front of them. So this light looks good but it won’t stop you being hit from the back. Kickstarter: A Bike Headlight To End All Bike Headlights.
Oh, and roundabouts? Totally avoided, went on the footpath around it.