Mine have taken really well to the horizontal nipples. When I first introduced the bucket to them, they were terrified of the bucket (it had some bold lettering on it.) So, I left one of their current waterers in with them, next to to the new bucket. After about 24 hours when I was sure they were no longer scared of the bucket, I removed the other waterer. This was when they were about a month old. A silkie figured it out first and the others caught on by watching. No problems or leaks since then and when I moved them out to the coop this weekend, I made up a new bucket (solid white this time) and they knew exactly what it was. I'll be using a large one in the run (5 gallon) and keeping my current one inside the coop (2 gallon) - this way I'll have a backup and won't have to move stuff around if I want to keep them in the coop all day due to bad weather, etc.
(I have 3 nipples on the 2 gallon that is inside the coop and will put 4 on the 5 gallon one outside. I have the 2 gallon one next to a wall, so no reason to add a 4th nipple to it.)
(I have 3 nipples on the 2 gallon that is inside the coop and will put 4 on the 5 gallon one outside. I have the 2 gallon one next to a wall, so no reason to add a 4th nipple to it.)