After three weeks in Germany, I have the conclusion that it depends. What beer is being brewed, on what system, and other factors. Helles, yeah LODO is great. A Dunkel, maybe not required.
I was at a brewpub that had copper vessels from what I could tell, pretty simple system. The Helles had an oxidized flavor, so there you go. The Mandarina Pils was good, I didn't detect that flavor. The export Dunkel was super, full of yummy Mailliard products.