I'm a big fan of the Brahmas, too. They have such a calm, sweet nature and beautiful to look at - my first experience with feathered legs/feet. I have 6 Lights now 7 weeks. All still have some down on heads and necks, but bodies are pretty well feathered. I can't make a comparison because I only have the one breed, but their development seems pretty normal to me. Certainly hardy little girls. Their bodies were pretty well feathered at 4 weeks of age. They went to the locked-down outside coop for a week and I turned them loose in the run at 5 weeks in cool (50-60 degree) temps. Heat in the coop, but they prefer to spend their days outside in the run, so long as it isn't raining.