I wouldn't know but I'd hope that it would be. True, Kunifer has a longer life and I've heard that when 'Bundy' goes rotten it's a 100% rip/tear fail, hence the developement of the aforsaid alloy.
However maybe there is a break for cars over a certain age? Can't see a Pebble Beach Delage or Bentley with squirrely 'on a coil' copper pipe. (I know, good kunifer, even on a roll ) or straight pipe if it exists, comes with a traceable batch stamp on the tubing itself but its still bright copper colored bent or straight).
I was at our national meeting last week and there where 'concours' cars with polished
copper pipe all over the engine bay; looked like some kind of Frankenstein mix of Rootes engine and steam donkey hoist.
If you have copper then no prob just dont shine it up. As my dear old white haired Granma used to tell us kids, ' You can't polish a turd'
No offence to you guys with copper; I've got copper like you but I'm going to bin it. It's extre cost and effort but it looks right. You might as well go the extra yard. After all by the time you have got the Copper coil; tried to staighten it; fitted it (and it still looks like a bodge); you might as well have got some bundy for the same money and done it right.
All joy to your endeavours
Oliver