I DO NOT think it matters a whole lot anywhere in the world. My choice has always been the .30-06. IN places such as Alaska, Africa, and the Northern Tundra, many choose the .338 Mag.which offers more "Steam". I base my statement of the .30-06 as also being easy to find ammunition for just about anywhere you may be. I feel it is the most certain caliber to also be able to feed.
* My personal choice as MY primary hunting rifle is a Remington 700 Varmint Special re-barreled to .30-06. What I end up with IS a heavy rifle, I always say "I do not mind this, no worries, to have this ability, I will haul this rifle where I need it". The high level of accuracy has so many times saved me miles of walking. I can take shot I normally would pass on, because I have absolute confidence I can run a bullet through a small opening in trees, I know I can place a shot to kill quickly and save steps tracking a wounded animal.
* It is said, "Never bet against a guy who only owns one rifle". The wisdom in this statement is that the guy has a TON of experience since he has shot this rifle many times and so has gained allot of actual experience with this particular rifle.
ADDED : I am a fan of the head shot. Using the ears as a reference to place a shot. OR a shot to the base of the skull to sever the spine from the skull. This way I ruin NO meat. MY moral specification determining IF(?) I will take a shot is I will ONLY shoot to a distance where I KNOW the bullet will strike within 3" circle of my point of aim. With this rifle AND my handloads, that would translate to 300 yards. I would NEVER, have never taken a "Hail Mary" shot on ANY living thing. That is TOTALLY against my morals.
* I always say, "if I can not do this, I will wait for another day another way, when I do have my comfort of making a GOOD clean shot". I have NEVER lost a single animal I have taken a shot at. So far, I can rest easy, I have been fair and done the right thing. I place MUCH in SPORTSMANSHIP. A Sportsman IS NOT a slob.