I have had both breeds from the strains you are getting (when it was Whitmore Farm). The Welsummers were clearly better layers than the BCM, and I was not able to tell any difference in egg color or size. That varied a lot between hens, and even in a single hen over time. The BCM were abysmal layers, in a flock of 6 hens, I was ecstatic to get more than 5 eggs in a week's time -- from the entire flock.I want a “rainbow” basket and I’m looking for a dark egg layer. I’m considering between Welsummers and BCMs. I know BCMs have darker eggs but I’ve heard Welsummers are better tempered. And no, the answer is not “get both”. I’m looking into getting black/blue/splash Amerucana’s for colored eggs and black/blue/splash LF Cochins for broodiness.
I’m ordering the Amerucana chicks or hatching eggs from http://deerrunfarmmd.com/. The have Wellies and BCM as well.
I have this farm's Delawares and am pleased with their vigor and size (not so pleased with how bossy and pushy they are). I also like that they feed their chickens all organic feed.
They breed their Marans to the French standard and the keep both black and blue copper varieties. Although their Welsummers lay terracotta colored eggs instead of "chocolate" I am considering them because they are an autosexing breed and the breeders admit their Marans don’t lay as well as their 3 other breeds.
Get the Welsummers, you will be happier with them.