Just thought I'd share about mine. My SC ladies got frostbite the first night it got to 30. Here, we get over 100 in summers and both RC and SC did great. Now that we're in winter, my RC leghorn is out in an unheated shed and we've gotten near 0 at nights, she is laying a HUGE white egg every day. The SC lady is in a heated shed and has just now started laying again after 2 months of being off due to her incident. So, overall I would say that in my experience with light brown leghorns, the rose combed birds are much better in the heat and cold
Exactly what I was looking for, thank you