I have 3 danish brown leghorns and one black australorp. I got 3-4 eggs most days all winter, though eggs have slacked off a bit in the last couple of weeks. The BA lays 6 a week, still. I haven't weighed them but would say the leghorn eggs are usually large and the BA egg is XL.
The BA is much calmer and friendlier, too.
The BA is much calmer and friendlier, too.