Hi ,,,!!
Yes I have 6 mixed breeds hen , 7 rhode island red hens and 2 roosters and yesterday I bought a pair of black copper marans (French) they are 5 months old And I just love them !!
I decided to buy them because I'm crazy about the egg color I loves brown eggs and my RIR lay light brown eggs not dark like the marans
I used to have some Cuckoo Marans and the Marans certainly do lay beautiful chocolate eggs. Good luck with your flock.