I have some 4 week olds and yours have more feathers than mine.  At least 4 weeks maybe even 6 weeks old.  Mine, too, are eating like crazy!!! I agree the BR are boys.  Look at their faces and if you see wattles then they are boys.  Look for a orangish/redish/pinkish color on the comb and my boy's combs are twice the size of my girls.  The combs stand taller.
Good luck, they sure are cute!