I have 2 polish (one black with white crest and one silver laced) hens in a mixed flock of 7 other hens (Barred Rock, Buff Orp, Golden laced Wyandotte, Easter Egger) and one rooster (black australorp). Mine have not started laying yet, as they are only 18 weeks. However, I can attest to and agree with the comments from the other posters- my black and white polish has been picked on horribly by my rooster first, then followed by some of the larger hens. I just had to remove her to let her heal up and get strong again. Once she was gone, I saw my rooster try to pick on my other silver polish girl. While I love the polish- they have great personalities, are friendly and docile- I wish I would have known about the bullying between breeds before I bought them. I think it's wise to have either all polish or all others. Good luck with whatever you decide.