I used one back in the 70's, don't know the brand.
It was adequate for me. Specifically, riding my bike down an unlit street with potholes. The light was adequate to let me see the potholes before I hit them. Probably was riding 10 mph or so. I wouldn't want to go too fast depending on one of those.
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"be careful this rando stuff is addictive and dan's the 'pusher'."