I've got 2 of them and never had a problem. At one point I bought one of their metal ones and it leaked. I think it was 3 or 5 gallon. I even cherry picked it to make sure it was the best of the bunch. Some of them had really bad seals. I ended up returning it with no problem. I like the plastic waterers and feeders because you can quickly see how much water/food is left.
If you hang the waterers and they leak I defiantly would take them back.