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I like using my BigBlue 1200 Lumen. It is not the cheapest torch but very good quality.
Don't have direct experience on this topic, so maybe someone that does can chime in. I would have thought a brighter (higher Lumen) light, of say 2000 vs 1000, could be detrimental in silt water as it would just highlight more of the silt, not necessarily go further through it. Kind of like high beams in fog or blizzard conditions are actually worse than low beams. Not sure where the line would be though!