There is every reason to be cautious about an old shotgun, especially with Damascus barrels. That being said....there is often more than a little over cautiousness. If a vintage shotgun passes inspection, there is no reason not to use it, especially with shells - as noted by RSI - designed for older shotguns.
There is a very informative article by Sherman Bell about "tests to destruction" that he did with Tom Armbrust. The tests involved a number of guns and included damascus barreled guns and modern proof loads.
The damascus barrels faired as well or better than more modern fluid steel, etc., type barrels.
I don't recall the issue of the magazine (The Double Gun Journal). Will look it up if anyone is interested.
"Only hunting and mountain climbing are sports. The rest are just games." - R.Ruark
NRA Life Member