The best gun you can use is the one you have the most confidence in! Having owned 7mm's, .300 win mag's and 30-30's . . . I now use a Savage .308!! I have 3 elk, 5 deer, and 2 antelope in the freezer over the past 2 seasons. The longest shot was 285 yds and the elk fell in his shadow!
It is one of the most popular calibers for bench shooters because of it's inherant accuravy at long distances. Best of all . . . it is fun to shoot. Shooting more means shooting better and you can't do that with a magnum of any kind. At the range they will spook your shot every time you try and squeeze the trigger. Not to mention your shoulder.
So I have the most confidence in the .308. If I ever get a Moose tag, it will go with me. I have used 168, 165 gr and 180's with very good results.