I tried guinea fowl once in the past.
Bought 9 juveniles.
They escaped the enclosure, I watched one of them fly vertically up into the air above the tree line, then it flew east until it disappeared from view.
Not good for the native insect eating birds the added competition but I'm sure the foxes are keeping them in check anyway.
If you ever get guinea fowl, clip their wings, it takes awhile for them to get settled in.
But if I had like 30 guinea fowl living in the garden I know there'd be practically no rodents or snakes in the garden and that would be convenient.