Not exactly loads of experience. I have gone through close to 2 dozen guineas in 3 years. One of my yappy dogs ate a guinea hen (oh look, a squeak toy that turns into a snack!) and I've lost quite a few to fox. I had whites for 2 years and they tended to follow whatever was moving (dogs, cats, cars) like it was their mother. The french, so far, don't seem to have this particular lack of survival trait.
I have the same problem with each batch of guineas not wanting to leave the pen, which makes them pretty useless as tick/snake patrol, so I drive them out and shut the door. I try not to let them back in at night. I get tired of the chase me around the pen game every morning. But some sneak in with the chickens and I let them be. Mostly, they roost on top of the chicken pen. I have not, to my knowledge, lost any at night.
I've just given up trying to keep them safe from foxes who come by during the day. The only way to do that, keep them penned, destroys their usefulness. So I just reconcile myself to the fact that some will get eaten every year and I buy more in the spring. I'd love to know what bluetick's neighbor's secret is.
The best source of guinea info I know of is here:
http://www.guineafowl.com/fritsfarm/guineas/
