Pros: lots of eggs, interesting appearance, alert
Cons: small eggs, can be very skittish, fly a bit too well
The smallest of my birds they were the most "nasty" to the other birds in the brooder, continuing until
the other breeds grew significantly larger. As of now they are all 9 months old. They are not friendly and don't get underfoot. Over time they are getting closer to me as I go out into the yard. They were the first to "escape" to neighboring yards, and at that point were too stupid to return the way they left, ie flying, and would fun along the fence cackling in dismay as the little flock moved to another part of the yard. They are flighty but not interested in getting away. Over the last two weeks they have figured out how to fly back home so my life is a bit simpler. The one snowfall we had was 4" a few weeks back, it has been a very mild winter, anyhow that morning when I opened the coop nobody ran out in the snow. A half hour later I looked out the window and saw the two Hamburgs strolling back towards the house across the lawn. The snow was deeper than their legs and snowing was falling on their heads and they they looked quite comfortable and undisturbed by the whole affair.
They fly well, perhaps too well, I saw mine blast over ten feet high while clearing a six foot fence getting away from a dog. But they are homebodies and generally the first to climb into the coop at night. Since they are my only flighty breed and the rest stay in the yard they don't go far. They are attractive and regular layers though the eggs are presently peewee to small, that may change as they get older and days get longer and warmer, I don't know since these are my first birds.
I wouldn't keep this breed in a run, confinement seems to make them nastier. They seem at home with room enough to fly a bit, scratch around a lot. They are the ones still out scratching when the rain picks up enough to send the others back to the run.