I bought polish from a guy a month ago, who was selling them because they were getting hen pecked on their crests, leaving bald spots. Other chickens can be quite mean to polish, which is why the other person mentioned isolated. Their crest limits their visual field so they can't dodge as well. My hens are mostly pecking at the rooster who still has a bloody crest, but they are leaving the hens alone and they are growing their feathers back on their crowns. But they are SSOOOO sweet and tame. I have had no problems with the rooster who is getting bolder, but usually runs away from me.
I am hatching their first batch of chicks tonight! My first hatch ever! So far the two out of the shell are doing fair, the polish seems to be steadier on its feet than the polish/BR cross. CUTE little guys! The polish reminds me of one of those dinosaurs with the domes on their heads except with fur. You can already see a crest and the nice deep nostrils that make it unique. He/She was the first to pip and had no trouble zipping out, but was pretty floppy and wobbly for the first hour.
Good luck!