Nick,
I’ve owned several Chapuis double rifles through the years. I’ve never had a bad one, some shoot better than others but all of them shot good enough for a double. I had a 375 belted that would put both shots (left and right barrels) touching at 100 yards . With factory Hornady ammo !! (I wish I’d have kept that one). As others have said “look at the bores and over all condition of the gun” . And, as with any double, it’s got to fit you or it’s no good. They are very well made guns at a very reasonable price point.
Good luck ,
Robert