The cookie tin thing works sorta okay, but it rusts quickly and if you try to paint the inside I was worried about it possibly catching fire. That idea lasted one winter.
I have had this heated waterer a couple of years now and it works fine. I keep mine outside. If the plug is grounded it doesn't bother me to plug/unplug to clean and set it back up after cleaning. If it's too cold to clean at the coop (where I normally have a hose and everything), I just take it up to the house, clean it and refill it there and bring it back. Makes for about 10 extra minutes of work...big deal. It *is* a bit flimsy, so getting the hang of filling it and putting it back together without it coming apart on you will take a few times, but once you have it mastered it's no problem...beats taking water out who-knows-how-many-times-per-day in the winter (and since I'm disabled and walking is a pain...literally!) this heated waterer has made it a good deal easier on my back.
If it's raining and you're worried about the electrical thing, keep one of those rubber bowls out with water in it so you know the chickens have something to drink until it's dry enough to clean and refill the heated waterer, but as I said, I've had it outside for a couple of years now, in all our winter weather (we just got done with some bad heavy rain that has saturated the ground to the point I sink an inch or better even in established grass yard) and have yet to have a problem with the electrical part of it.
