The Remington 600 was mostly a marketing failure and never caught on. However the 350 version was very popular in Alaska. It was a light handy rifle that packed a big punch and could handle the bears.There was a guy on another forum I used to spend time on that lived and hunted Alaska with a 350Rem Mag. I don't remember the rifle used but he had posted many pictures of Moose, Black, Brown, and Grizzly bears, Musk Ox, Caribou, and others. He would always say it would put them down as quick as the 338 Win Mag.
I have been looking for an older left handed 30-06 for several years that I can send off to JES and have it rebored to 35 Whelen or Brown Whelen.