As I was researching if I wanted quail, pheasant next.... I have had chickens for years. This is what I learned and what I chose.
Is this assuming all things equal? You already have a preditor proof structures for which ever bird you choose? I agree with Robo, pheasant is out right off. They are harder keepers, needing flight pens, expensive to buy, not pets at all (from what I read). Bobwhite quail too out as as a pet bird.
Yes, between quail and chickens...
I cant raise a chicken to eat for less than I can buy in the grocery store. I figured it out with my last hatch, It cost almost $5 per bird. Not bad, but not as cheap as the store. Although it does taste MUCH MUCH better!! And of course the eggs are great, can sell the eggs and that offsets the cost of feed. I break even with selling eggs. Chickens are neat creatures to watch, they all have personalities, they make you laugh with how silly (stupid) they can be. lol As so with quail. Quail dont take as much space to raise either.
I am new to cotournix quail, but so far, I am in LOVE. What an awesome little bird! They grow incredibly fast! Will lay eggs in 6 weeks (versus 16-20 weeks for chickens!), butcher size at 8 weeks (versus 16 weeks for chickens). Chicken being readily available anywhere, quail are not, but can be raised for meat cheaply.
So it depends really on your facilities and what you really truly want them for.
Another option is guinea's too. That will be my next venture. I hear they are great for tick patrol, and other insects. I can raise them for the same price as a chicken since they need the same feed and coop. And they reportedly taste like pheasant!! So, I can raise a high price (restarant) meal for $5 a bird? Wow! And will control the ticks which I have an issue with getting on my horses, dogs, and cats. Another great choice. (although they are noisy birds too). Again it depends on all your specific situations.