I say leghorns because I've only got one pullet laying right now, and she's a champ. Last time I had chooks, I had so many laying all at once that I couldn't tell who laid how many. I could, however, tell my leghorn eggs apart from the rest, and they laid more per bird. I never had a barred rock that lived to lay an egg (my one was killed by a dog), so I don't have that experience. I have 2 in the henhouse right now, tho, that haven't laid an egg yet because they're only 17 weeks old.