Thus far, I am pleased with my Guineas. I will say one thing: they are NOISY but not a problem for me. I have 14 Guineas hatched & raised last August by chicken hens (13 are Pearl with 2-3 w/ a few white primaries & one solid white Guinea). I believe I have 4-6 males and 10-8 female Guineas. I free range Chickens, Guineas, Geese & Turkeys. All get along pretty good. The Geese rule everything and chase & pull more feathers than all the rest combined. I also have two good mutt dogs that keep away the predators. The Guineas and Chickens put themselves up at night and roost in the same large coop (I close & lock the door when I get home at night). Some Guineas roost right beside and with the chickens in the coop and some others roost up high away from the chickens. Sometimes, one of the turkeys will join them. Otherwise, the Geese and Turkeys stay out 24/7 and Turkeys roost in the rafters of some open barns; the Geese like to stay up all hours near the house but they have a barn they go to (where their nest is & they think is theirs).
I have noticed a Guinea chasing a chicken hen here and there but I also see chicken hens chasing other hens. The Guineas seem to adore the rooster who is out and he likes all the attention. They follow him everywhere. The only blood I have ever seen drawn on my place is the occasional chicken rooster getting out who doesn't get along with another rooster (and that is just a cut on the comb). When they are free ranging, there is plenty of room to get away for any bird being chased by another bird. I realize that it all might change but I am hoping Robin416 is correct about the 10-plus rule. I need the Guineas for tick & Japanese beetle control. I hope they brood and I can increase the flock numbers. Since mine were raised by chicken hens, they seem to still adore the hens that mothered them & they see the big coop as somewhere safe and to escape to -- I've noticed.
The only weird things that have happened (that I have been home & observed), two things: First, was one night I heard a big commotion in the coop & I went out there and Guineas were flying around crazy-like in the coop & haphazardly slamming themselves into the walls and wire. I just knew someone was going to get killed by accident. I looked around real good to see what had spooked them but didn't see anything. It was near New Year's so I was thinking maybe a distant fireworks sound. Nobody got hurt and all was well the next day. Second thing, for whatever reason, the Guineas grouped together one day like a big gang and then as a flock, advanced by ground on a neighbors house (some distance away), inching forward , clamouring louder and louder as they approached. Once there , right in front of the neighbors house, they like doubled the noise. It was real loud. The neighbor was alarmed, came out, clapped her hands one time & that sent the Guineas to take flight and fly home.
Is there a good book on Guineas that explains their nature? I like books.