Which lens do you think is better for sight fishing as well as all-around fishing in various light conditions, the green mirror or silver mirror?

Copper or Amber.  Sorry, it's not one of the two you listed IMO.

Of the two, silver mirror.

But yes, copper or amber would be a better fit for an all-around lens.

Both the silver mirror and green mirror are copper based lenses with a different coating. I just picked up a pair of green mirrors because I could not find silver mirrors in the frame I wanted. I guess I would have to go with the silver mirror if given the option, but my green mirrors are fantastic and you will not be dissapointed with either.

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If your purely looking for spot fishing I would go with Amber.  I have a set of blue mirrors and love them for an all around lens.

GO BIG RED

The green mirror is copper-base in the 580, amber in the 400.

The mirrored lenses transmit about 10% less light than the non-mirrored lens.  My next pair will probably be silver mirror, but I don't think I could find a better all-around lens than the amber 400.