I was interested in the .338 Fed also. It seemed to have the edge over its bigger sibling the .358 Win, as there are better .338 bullets out there than .35 bullets. More variety in the premo line.
I never committed to a rifle, in .338 Fed or .358, as I realized I will likely never hunt anything that my .308 will not handle. But.......the .338F seems to the mid bore that the .358 wasn't.
Same, same, but aside, I looked at 338-06 as well, as opposed to a .35 Whelen, and again, ... what would I ever shoot with it?...so I didn't buy.