Thinking of using corrugated metal in a new bathroom

[Warpy]

4. I live with extremely hard water and that's the first thing I thought, too

The only worse one would be those river rock walls that movie stars are having installed in their showers. I'd be especially leery of using hard water stain removers on it unless it were corrugated stainless steel or chromed steel and I don't even know if those are available.

It looks like one of those ideas that's great if you only intend to be in the house for under five years, then you sell the house and let somebody else figure out how to clean the faddish parts.