I don't remember if they were slow to feather. Initially, they had a lot of white feathers, but as they've gone through their juvenile molts, the white has been replaced with the nice dark mahogany. One of the cockrels has a lot of black feathers, so will most likely be on the short list, as...
I have 6 BE in my flock of hatchery birds this year. They are the smallest in the group. However, I am pleased with the spunkiness of them, and they are now developing the nice mahogany color that the breed is noted for.