I'm only 2 weeks into owning quails - and started to raise chicken.
My wife dropped 35 adults quails on me one day and I had to build cages for them. From what I understand, quail does not need a run but they do need space in their cage. 1 square foot per quail and at most 1 male to 7 females.
As Violamana stated, the noise factor is not that much, the male is not as loud as a rooster and the female sound more like frogs.
EM TY had a pretty nice set up, slanted 1/2 inch wire floor to help collect eggs makes it much easier then opening the door/lid all the time (I have both slanted wire floor cages and solid flat floor cages).
They do produce a lot of droppings!
What I'm working on still right now is to keep them from pulling each other feathers out

so sad, the back of my birds are mostly featherless

- I increase them female population to 1 male for 10 females but still doesn't seem to help. That is something you most likely will run into once they start laying.
Egg quality, from my research does have a higher protein contain than chicken egg. about 3 to 4 quail eggs to a Costco chicken egg.
Our 1 and 3 years old daughters loves looking for and collecting quail eggs.
I did have to end a couple of male quails and found the meat to be more chewy than chicken meat.