I will repeat what the others repeat--you need to talk about material specifications, not trade names. If the terms are being used generically, then it means absolutely nothing to quibble about corrosion data for one trade name vs. another. In the end, these products are manufactured to a published standard, and they are under no obligation, no matter what past data may show, to produce to any level higher than that standard. So either the published standard (for whatever brand you buy) meets your requirements, or it doesn't.
Right now the only COR-TEN[®] products I see listed on the U.S. Steel website are roofing materials. I can't even find "Xten", but maybe I'm just searching badly.
Hg
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