I'd take the 458wm and the 375H&H. The 458wm for your buff and the 375H&H for the plains game or just in case you had a problem with the 458wm. You have both and traveling with two rifles isn't anymore trouble than with one, imo.

I also like to be carrying an elephant or buff capable rifle when they're around. A soft up the spout and solids below.

JPK