I also like the dual purpose, but we only have enough chickens to supply eggs for my wife and I and give the extra eggs away to family and friends. I know it gets cold and very hot in all of Idaho, but as long as they have water and shade they should be fine. We have always had the traditional dual breeds and had good luck with them. RIR, Plymouth Rocks, Wyandottes, etc. although the last couple of times we raised chicks we have gotten to like the egg production from white Leghorns, I think they will lay 30 or 40% more eggs than dual breed. But again we have 5 birds for two of us, eggs only. As Dun stated you don't have egg layers to save money, I figure our eggs cost us 4 to 5 dollars a dozen, included the price of the coop and repairs, i don't want to think about it. Plus in our area free range birds won't last the night between the Hawks, Eagles, coons and yotes. I have a neighbor a couple of miles away that never learns, seems there is a pile of feathers across the road from their place three or four times a week.