If they had blue feet then they would look just like my Cream Legbar x Bresse hybrids. I love the white crest. But personally I think it is going to be difficult to remove the white sports from the flock. Others will probably speak up about this. My Cream Legbars don't have that in them. I culled heavily to improve the flock and make it closer to the SOP. But if you do decide to keep them, I would recommend informing all buyers that your flock can produce them. Some people will not want to have to deal with white sports popping up in the hatches.
I agree - buyers would need to know - that is one of the reasons I mentioned the heritage of my flock - other GFF owners may see this pop up as well. I'm wondering if this gene is more prevalent in the lighter colored stock - As I said, this is 3'rd generation before this popped up.
Here is one of my adult roosters