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I have a Thunder Gray and I have to say it depends on the lighting. Unfortunately I don't have a ton of pictures (I am mostly in the car when pictures are taken ) but here is one I found that looks a little dark like in your top picture.
I don't think they have changed it. Car lighting is just about what it's reflecting. The white set makes the gray look lighter that a much darker black pavement, dark buildings and shrubbery.
) but here is one I found that looks a little dark like in your top picture. 
