Is stainless steel water piping more durable than copper?
In general, yes, stainless steel is more corrosion resistant than copper. It forms a tightly bonded oxide coating which tends to prevent further corrosion.

If replumbing a house where copper pipes corroded (this is more prone to happen in some areas than others due to water chemistry differences) my first instinct at this point would be to use PEX plastic tubing, but for metallic piping I would choose stainless steel over copper even if the price was the same.

If on a water supply that is treated with chlorine, or which has salts, there is a slight possibility of a stainless-steel specific problem (chloride corrosion). Certain grades of stainless (316, 316L) are more resistant to this form of corrosion than other grades of stainless, so precisely which stainless piping you are being offered will matter.

Still, I'd choose PEX by preference - should cost less, and it's not going to corrode.