I remember seeing ads for Rheem glass lined tanks (porcelain) in the 50s. One of their water heaters was called a Rheem Fury. I thought that was a neat name. Copper got too expensive except for super TOL heaters. Monel metal tanks lasted forever partly because they did not have a flue going up through the tank; the heat went around the tank. Generally the burner assembly or the valve at the bottom failed and that was why the tank was replaced.