I have a galvanized 40# hanging feeder in my coop and a 5 gal galvanized waterer. I haven't tried heating the water yet in my coop (it's a new one) but that is the right kind of waterer to heat. My waterer is about 8 inches off the litter to minimize the mess.
You can't put Apple Cider Vinegar or Vitamins (probably electrolytes either) so I am thinking of getting one of the big plastic waterers to do those things out in the run. I keep water in my run in a feed dish for my llamas, it's easy to clean and refill. I'll probably continue with that one in case some of the chickens don't care for whatever I add to the plastic one... When it's really hot I fill a tub just a few inches with cold water in it to stand in and add it to the run. I also plan to add a range feeder once I totally predator-proof the run so I don't have to worry about attracting vermin.
I bought all of my feeders/waterers at local feed stores, but do compare, they do vary in quality and price. Shipping usually negates any savings on ordering online with these larger items, for me...
Patty N. ;-)