Mine are 17 weeks and look similar to charley's. Good to know that they would have been obviously boys a while back. Since I've read they are slower maturing, I didn't know just HOW much slower and how that would affect when one knows their bird is NOT a boy.
I think it is different between hatchery quality and show quality birds. My pullets are hatchery quality and they tend to be smaller as adulthood then show quality birds. This probably makes a difference in how early you can tell if they are roosters or hens.