What little I know is that my guide for my hunt in a couple of weeks is more than pleased that I am bringing a 375 H&H loaded with 270 gr TSX's. His words, "perfect".
I am sure he is pleased as that is the reference standard for big bear rifles. As I said, when a client askes what to bring I first ask what they but if they have already decided that a brown bear hunt in Alaska is a good reason to buy a new rifle I suggest either a 338 or a 375.