Kai: Which is for you? Although it’s best to do your own research and get multiple opinions on the subject, our personal experience boils down to what our original plan for these types of birds was, which after a year’s experience, we still find to be the same.

As novice homesteaders, we were not ready to butcher our animals, and chose to have “pet Chickens” with the additional benefit of getting fresh eggs. This worked great, and our hens lay often enough, though they can be easily stressed into not laying. They can be trouble makers, and do require a lot of space, but they can also be easily sustained with forage.
They are intelligent, trainable, and durable.
And although we have not bred chickens before, our hens do go broody time to time, so we at least know they’re capable of possibly raising chicks on their own.
They are great for composting your yard debris, and will till a garden space for you in no time. Large chickens will kill and eat snakes and rodents.

Quail (coturnix) are definitely good for smaller spaces, and in our experience, they are extremely good layers. They are a more manageable size for those new to butchering, and can be kept in various types of containments without problem. Some are kept in cage stack systems, some people keep them in aviaries, and if you’re like us, we used open-grate rabbit cages.
However if I know anything about quail, they are certainly far from chickens in terms of trainability, and they certainly find unique ways to kill themselves. They are easily spooked, even if you raise them from egg. This is simply the nature of quail, and on top of that, much of their natural survival and parental skills have been lost. There are some that say they will go broody if kept in a large enough aviary.
I spent a lot of time artificially incubating over 70 eggs before finally hatching 8. Not sure if this was just beginners trial-and-error, or perhaps the genetic quality of our birds, either way, it was a difficult learning curb. On the flipside, a testament to them being awesome layers.

These are just a few of the pros and cons of raising these particular birds from our personal experience. I’m sure there are many of you out there who have much more insight and years of experience than we do. Its always good to expand, share and update. Let us know what you think. And we too will share our further finds!