Rare Breed, rookhawk & Mtn_Infantry,
I'm looking at something along the lines of a .375 Flanged Magnum or .450-400 3" NE, as the only DG it might ever be used for would be Cape Buffalo. However, since said hunt would likely be a one-time thing, I would probably play it safe and take a scoped bolt gun. Plus I figure those chamberings would give some more flexibility.
I doubt I need a 470 NE for a Buff hunt, and it wouldn't be legal for our dangerous corn/soybean infused Ohio Whitetails. Although, a .450 3 1/4" NE or .500 NE actually would be, as well as a .458 WM/Lott. I digress.
The smart thing would be to buy either the Chapuis or Krieghoff in .375 Flanged that Champlin has due to caliber, price, and knowing that they're GTG. The Chapuis in .375 H&H makes even more sense as I wouldn't be locked into uber expensive and/or hard to find ammo or reloading. I can do the latter, FWIW. I am aware of the potential issues of a rimless, high pressure cartridge in a DR that could come with the H&H.
They have a Chapuis in .450-400 also. FWIW, the 375 Krieghoff catches my eye of those options.
However, a vintage Birmingham gun is what calls to me. I truly don't care whose name is on it, or that it's that fancy. I'd wouldn't mind finding a solid Army & Navy DR. Of course there are the risks that come with a vintage gun, and I'm not at all familiar with the process of finding someone to vet it, getting a seller to allow it, and then actually getting it done.