I haven't tried green yet but own both (high-end) grey and copper. My retinas disagree that copper is unilaterally better than grey as a blanket statement.
Copper is better for contrast flats spotting situations. Grey is better when color is key and contrast is not the visual queue.
Could be the northern flats striper angler faces more color-based situations than the tropical angler, although I have taken advantage of / suffered from both in either situation.
I have been in situations where the subtle green color tones of the slow-cruising slack current ghostly bones over marl are the only clue of their presence, but it's much more common for me to queue on movement by color on Monomoy's grainy sand flats.
I'm curious to try the greens but not expecting quite the returns the hype would lead us to believe.
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