The 2 AO Smiths were installed in my house in 1977. I replaced one 4 years ago, the other 3 years ago. The house was on a well until 1984 or 1985. There is no visible cues that a water softener was ever installed. I try and drain the tanks once a year. Sometimes I forget.
If I would have changed both at the same time, I would have saved a few hundred dollars. The price went up, as the water heater became "smarter".
