I used Countryside Organics for a while. I found the shipping expense made it very pricey so I switched to something closer.
Also, it is not a pelleted feed, and the ducks were able to get more of it when I moistened it. This made it more important to keep track of how long the feed had been out, because I did not want it to mold. But dry, the ducks had a hard time getting more than the field peas.
If I lived closer to the source, I would probably use it again. A friend with chickens raves about how her flock health and egg quality have improved with this feed.