The e gene series affects the chick down colour and the adult colour. They will probably all end up partridge, but the lighter chicks are either eb (brown, do they have darker heads? ) or - eWh based (wheaten) (are they yellow with reddish down tips, like toasted marshmallows?) and the chipmunky striped chicks are e+ Wild type duckwing) . The e gene series works with some other genes to put the pattern/depth of colour and colour on the feathers and the extent of red and black. There are slight differences in the adults, based on their e series genes, but you probably won't notice much difference in the adults because there are a whole lot of other genes that affect the outcome. It would be worth marking the chicks to see how they compare as adults, if a certain down colour produces the adults you like best, you could select for those in future generations.