I've raised the hens both free ranging and in pens and had better luck in the pens. If you can kill all the predators in the area free ranging is great. Just remember some of the predators will have names and be wearing collars
Quail can be difficult to get to adult size if they hatch too early or late in the season but are easy to keep once they are mature. I'll try to find online plans of the funnel shaped return hatch that let's them free range all day then go back in at night and not be able to get back out. Just don't turn all of them out and the loose ones will come back to join the caged ones.