RE: 280 rem or 270 win
They are so close either would do, both rounds are common if using store bought ammo but in that case go with the .270 win as the selection is greater. If reloading get the .280 rem because there is a greater selection of 7mm bullets out there. I personally like the .270 win even though I reload, no other reason than it is an old classic and I have used it for years.