From the ones I've received, (so far) it appears light grey with no dark head, flesh colored beak and legs, are roos. That's not to say that SG roos can't have the darker beaks and legs as in the Hoover photo, it's just saying that mine do not. All of my females (if they truly are females) are a shade of grey...from medium to almost black. SOme have completely black heads with yellow throats and some have dark heads with yellow and black banding in inconsistent patterns around the eyes. All have either dark beaks and legs or flesh colored with splashes of the darker color. So in that box with the marans you posted, there is 1 with the same coloration as my roos, and 4 others that could possibly be roos based on the lighter grey plumage...though all of yours seem to have the darker splashes of color on their beaks. In the case of my batch, that could indicate females..OR...the Hoover photo is accurate and the lighter plumage paired with dark beak and legs could still be a roo

Mine start their 5th week tomorrow and the suspected roos are roos...beyond any shadow of a doubt. I have one probable pullet that I still question somewhat as her comb is larger and she has a more solid feel like her 2 brothers. Though her markings and coloration scream female. I've found that all the typical markers aside, I can sometimes pick out a roo just by closing my eyes and picking them up....they have a different feel. In addition, they have a way of cocking their heads and glancing sideways to observe something that is just different than the way a pullet does so. So I want to see how this particular girl observes her environment and see how she feels when I lift her out. It's really hard to gauge color from the overhead shots into the packing carton that you posted. If you get a chance, maybe snap some pics of them lined up on a surface in daylight

Then we can play the guessing game! I love the guessing game!