the ACV with mother is good. Really it doesn't take that much longer to ferment than not. I currently have 80 birds; about 30 or so are adults and are fed once in the morning. The rest are babies and juveniles that are fed twice a day, morning and evening. Morning chores including letting the dog out to run and play, playing with the new kittens and feeding them plus all the chickens and rebooting the ferment buckets takes about 1-1 1/2 hours in the morning. I spend about the same amount of time in the evening feeding the babies, gathering eggs, playing with the dog and the kittens and filling up all the waterers.
Besides the probiotics the fermented feed is sort of pre-digested so the birds are able to absorb more nutrition from it, along with the healthy gut bacteria. When I started doing it almost two years ago my flock numbers were in flux, with hatchings, selling, culling, ect so I couldn't keep an accurate record but many people have done experiments, especially with their meat birds, and found that they use less feed when it is fermented. Some have even begun to ferment their dog's dry food and report less intestinal troubles, and way less rotten gas.