We bought one of these 13 years ago and finally have to replace it. We have two large dogs and hard water, but this waterer has held up. At one point had to "adjust" the connection which had began to leak but an ordinary hose clamp was the remedy. The bowl has been outside on the patio in the afternoon sun and never cracked. Periodically we do need to disconnect it and clean out algae, but it cleans up fine. We highly recommend this product. It has served us well. We are ordering our second one with confidence.
Does it work? Meh.. I took mine apart and installed it into another Little giant bowl that was mountable and also tougher (heavier gauge plastic). I have 3 large dogs, Great Dane big ;0) and they need water all day while I am work. This item is ok, however I ended up just harvesting the guts that I needed to make something better for my pups. All and all I am happy with it, but be warned the bowl is not that big, and could become a chew toy quickly, and it wouldnt last a minute if that happened.
Plus the price with shipping wasnt worth it to me to buy again. I personally think you could build it for much cheaper with some swamp cooler parts and buying a better bowl to start with.