For the Worldwide Big Game Hunter, there is no substitute for ammo availability should SHTF and your ammo is lost, stolen or you run out (having to sight-in after an accident or some other issue).
If in any given year I'm travelling to Asia, Australia/NZ, Europe or Africa (heck, even going up to Alaska or Canada) and spending tens of thousands of dollars on hunts, it's absolutely foolish to bring along a 280. You will not find 280 ammo. I will always find 270 Winchester ammo in some bullet weight or another and that's why my Model 70 in 270 Winchester is my all-around light deer/sheep/plains game cartridge; else, it's my 300 win mag or my 375 H&H or 416 rem mag depending on the scenario.
"The end of the human race will be that it will eventually die of civilization"-- Emerson
Support outdoor sports and our hunting-conservationist heritage; hunt with high morals and ethical standards