Dark egg layers can't lay an egg every day and keep the dark color, so generally, they are not like a production layer. Takes time to "paint" an egg. Welsummers lay a deep terra cotta colored egg. I have one girl whose egg is like that and the other Wellie's egg is a few shades lighter and very speckled, but a pretty egg nonetheless. I personally don't like the looks of the Marans I've seen, and with the inflated costs of acquiring those, I like the Welsummer for my dark egg layer, though some of my Delawares lay an egg almost as dark.