This thing has saved backs and sanity in getting water to livestock during our bitter Utah winters! Highly recommend if you suffer through frozen hoses when keeping horses, cows or goats supplied with fresh water. Could even be set up for a remote pasture is you right a solar/inverter/battery unit.
Where we are staying for part of the winter requires a heated hose. This appeared to be one of the best we could find for a decent price. It has not gotten below freezing yet but everything does appear to work. We only needed one about 40 feet long, but 50 feet was the the nearest size we could find. Being a 5/8" ID allows for good water pressure.
The hose functions flawlessly. However, the first month of use the water smelt and tasted like plastic. Even after filtering twice.. I even ran around 50gallons of water through before use.
It's not a cheap hose, but it was definitely worth buying. The hose is quite soft and has thick walls. It doesn't break like most crappy hoses. It is easy to install. The heater works great, down to 15F cold, which was at night a few days ago. After turning the faucet, the water flows out of the tap for a while rather lukewarm - it is obvious that the heating of the hose has a sufficient power reserve.
So far it has been a great product. No leaks and -30 weather and never froze. I bought a different brand a couple years ago and only lasted one winter. This item is constructed much better
Sue Bodily 
