With mine, the lighter breeds like Leghorns (all colors) Fayoumi, Sumatra, Hamburgs tend to range farther and spend more time looking for their own food, the Red Stars are probably the best of the brown egg layers I have. The heavier breeds like Wyandottes, NHR, Marans etc are more likely to wait for me to come with dinner. Interesting on the Speckled Sussex, I've had hatchery ones (still have two older ones now) and they tended to be pretty lazy birds, would not have put them on my list of good foragers. I have gotten some from a different hatchery and hatched some from shipped eggs this year, so will be interested to see if ones from different sources act differently. Also hatched out some SFH, do agree they look like they are going to be good foragers, they tend to be brave chicks and are doing a lot of wandering when let out.