I always figured a brown bear or moose hunt would be a good excuse to get anotehr rifle - one in .338 or .375, with a "magnum" of some sort on the end. Still do, although my .45-70 would fill the bill.
As a long time 7mmm Mag shooter I have to say that with the best bullets (North Fork, Trophy Bonded, A-Frame and maybe TSX), I would have no concerns about the 7mm Mag being adequate for either browns or moose.
For that matter, the 7mm Mag was my first bolt centerfire big game rifle and every one since has been redundant. But I enjoy them all.