They should be good layers and all brown eggs. In the background there is one with cuckoo pattern, and another looks to have dark brahma in lineage (poor silver penciling). The cuckoo most likely came from a barred rock back a generation or two. So basically the parents, grandparents, were a mixed flock of good to very good layers. Most likely was a Rhode Island red back there too, red leakage to one of the black birds. I'd suspect 6 eggs a week from any one of them, some more, some maybe only 5 eggs a week (the dark bird with silver penciling I'm guessing 5). But it's all guess work.
Mixed mutts are nice looking as there's such diversity and ya never know what will hatch from them.
