I'd been wondering about metal waterers because they look nice, and the plastic ones do wear out after a couple years.
Donna's wondering why I thought this would make a good photo, but this is the waterer we like:
View attachment 4288472
Between last night and this morning, I reminded myself of the 2 main reasons I've stuck with plastic waterers:
1. Our well water is potentially tough on metal, and I worry about zinc leaching in galvanized waterers.
2. We regularly have temperatures cold enough to stick to metal (for us, that's low 20s F/ -6 C). You'd think I'd learn not to grab coop keys with damp fingers or mittens

Handling metal waterers those mornings would be a nightmare, and I wasn't even thinking about the wattles!
Interesting to see how others solve for waterers.
@fuzzi -- I'd been wondering whether that water-bottle trick works after it started making the rounds on the 'gram reels a couple years ago. Looks like a clever setup.