I've been using this automatic waterer for my small herd of goats and chickens for about a month now, and here's what I've discovered.
The brass valve system works like a charm - no leaks whatsoever, which was my biggest concern. My animals quickly learned how to nudge it to get water, though my more enthusiastic goats sometimes bang it harder than necessary.
About that capacity claim... don't believe the 8-gallon description. In reality, it holds maybe 12 ounces at a time. It's more of a 'continuous flow' system than a storage container. This actually works better for keeping water fresh, but means you need a constant water supply connection.
The plastic construction feels sturdy enough for daily use. I particularly like the side holes that let me secure it to a post - stops the animals from flipping it over during their excited drinking sessions.
One surprise - our farm dog claimed this as his personal water bowl! The height and design seem perfect for medium-sized dogs too. Just be warned: in freezing temperatures, you'll need to bring it inside as the mechanism isn't winter-proof.
For the price, it's been reliable and low-maintenance. Not perfect for every situation (my horses need something bigger), but great for goats, sheep, poultry or even pets.