I have both, but the KC are just beginning their first lay cycle, and the eggs are tiny. I know the eggs will get bigger over time but I don't remember the eggs from my WH being so small at the beginning. The WH are supposed to be just a color variation of the KC, but all the descriptions say they are bigger birds. Is this true?
WH were developed from breeding a pair of light colored KCs in the 1940's. It was a mutation. The WH are larger than the KCs although my female was taken by a predator before she began laying so I don't know about the size variations in eggs. I can say that my KCs eggs were the same size as extra large to jumbo sized chicken eggs.
My welshie's eggs were about the size of a chicken egg at first, now significantly larger. So I think the welshies do lay a larger egg at first.