I really hate to scope a vintage classic double, as once done can not be undone. You really never own those guns, just posses them for a time. The next guy may not like it and it changes the gun forever. But if the gun is a shooter or a meat gun, aka Merkel, Chaphuis, Heym, I have no issues. Even a classic if done with claw mounts is attractive, to me. My eyes can not shoot past 50 yards accuratley. A 9.3, .375, or 450-400 is a great gun scoped, IMHO. Finding a Holland with original mounts is a bonus.
It really is a personal thing except that the future value must be considered.
John