One thing many will forget, or not consider in a survival situation such as Katrina mentioned in the original post is that it is an urban environment during a natural or manmade catastrophe. Sub -Umbra aludes to it with his very low light selections, learned in part, or perhaps better said, reinforced by his own experiences in the said hurricane Katrinas aftermath.
This means that after dark, the predators will be coming out, no matter how much police and national guard you have posted. If you are caught in such a situation, the last thing you want to do is draw attention to yourself with blazing lights. There WILL be a lot more of them than you, and they will NOT hesitate to take any advantage to get whatever you have they want, and they WILL want anything you have, just because you have it and they do not.
Low light, low footprint lights such as Covert Photons, Inova X1s (old spotlight version), and even the more more powerful RR 1 and 2 AA lights with the spotlight type beams, will be some of your most useful lights in such a situation.
Just some more food for thought
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