Ahh yes, guineas...great for tick patrol, wild as cooties, poor parents (but once the keats get on their feet and going, they can do okay, damp weather is a problem for them).
The eggs are a little pointier on one end than chicken eggs, the shells seem to be a bit harder also. But they're okay to eat, I guess, if you can find them. Nests are usually in tall grass (or, in our case, in the ditch alongside the road :?: ) Our predators (raccoons, I think) seem to find the nests the week before they're ready to hatch. When the hen is setting, I often hear her making a different sort of sound so that's how I find the nest. They lay 25-35 eggs in a nest, maybe more. When they hatch out, it seems like the whole troop of guineas help raise the brood and any one of them will come at you like all getout if you get too close to the babies. I've watched a couple of the "guards" looking up into trees for hawks and things while babysitting. Interesting birds, to say the least.
I was able to get a broody bantam to hatch out a couple of guinea eggs that the guinea hen left in her ditch nest by the road. One baby disappeared and then TWO banty hens co-raised the keat; that was one spoiled, well-protected baby though.
They'll do bug patrol in the garden also, but don't feed them anything you don't want them to help themselves to (like a spoiled tomato or something) cause they'll get the good ones too.
Watching the males race in endless circles on the hottest days will make you dizzy; but you'll have a good laugh too. Silly, noisy birds, but I'm glad we have them. They only miss a couple of ticks, if any.
These are just my impressions after having them around for a few years; you can Google "guinea hens" and get all the facts.