We recently got half a dozen of these little birds in a variety of colors to keep primarily as pets and egg layers.
Because we've seen such a huge difference in temperament depending on color, I will describe each below.
WHITES
Hands down our favorite variety. They are a good size, lay medium to large eggs, and are extremely bold and friendly. We initially got two, but both turned out to be males and we had to get a third female. All the whites are very easily handled and, when allowed out, don't try very desperately to escape our clutches. Our white female is actually very protective of her cage mate and has actually feigned injury to us to protect her (even though they are both girls).
The males we've had of this color were not male aggressive (meaning you might get away with having several males together as long as there are ladies to go around).
While not particularly important, our white male is the WORST tidbitter. He doesn't tidbit at all.
GOLDENS
In my eyes, the prettiest of the varieties. Their dark beaks and pale faces give them a hawk-like expression, which is aided by their generally bold but flighty nature. Both of goldens (one male and one female) are very watchful. Our male is tamer than the female, but neither are very suitable for holding. Their eggs are medium sized and they tend to be smaller than the other color varieties (bigger only than the wildtype color).
Males of this color can be very aggressive with other males.
Again, while not very important, I love that our golden male is obsessed with tidbitting. He does his best to look after his ladies.
TIBETAN
Our favorite egg layers. Our Tibetan was a big girl to start and lays large eggs (she has even given us several double yokers). She's a wild little thing but pretty. She shows the most potential for broodiness, which is important if you wish to have a bird raise chicks for you rather than an incubator. Our Tibetan hasn't been especially greedy with the food either, letting the male or her female cagemate eat the good tidbits.
We haven't had a male of this variety so I cannot say if they are good with other males or good with their hens.
WILDTYPE/PHAROAH
The least favorite of them all. Our normal girl is small, lays small eggs, eats all the worms (greedy), and is flighty to boot. I can think of no reason to get this color variety over any of the others, UNLESS you are getting a jumbo brown (this color variety but bigger). At which point, bigger bird, bigger eggs, and probably tamer.
We haven't had a male of this variety so I cannot say if they are good with other males or good with their hens. But again, I can't think of why you would get this variety when there are better ones out there.
OVERALL
One of the major pros of having quail is their size. Because they are small, they have smaller space requirements and can even be kept indoors. As a rule of thumb, 1sq ft per bird is acceptable but I prefer to give them 2sq ft. Even at this spacing, they are lawn killers. High ammonia in their feces combined with their tendency to scratch holes for nesting means grass will not survive unless you move their run frequently. This problem can be remedied by keeping birds in solid bottom coops raised off the ground.
If you don't clean their cages on a regular basis, be prepared for a mighty stench.
The second major pro is how fast these bird grow. They mature in about two months, so eggs and meat become available very quickly. However, this growth rate requires high protein content that is hard to find locally or even online. Wild, these birds probably eat a substantial amount of insect as part of their diet. Offering them mealworms, waxworms, crickets, etc that you can buy at the petstore not only provides interesting variety, but also essential protein to their diet. Alternatively, scrambled eggs or ground beef can help if you find your feed isn't high enough in protein.
Be sure that your feed is NON-MEDICATED!!!