IF: You are not affected too much by recoil. IF: You practice enough to take advantage of the extended range that a 300 magnum calibur will give you. IF: You don' t care about the extra meat damage. IF: You also plan to hunt Elk, Moose, or Brown Bear. Then by all means shoot as big a cannon as you like.
Me personally, I have gravitated more and more towards less gun not more. I hunt mostly in thick woods. A 200 yard shot is rare. I only hunt whitetails. I also love to target shoot at a gravel pit on my families land. I have shot a 300 magnum and a 300 WSM owned by friends and I own a 7mm mag that I bought years ago. I can shoot them reasonably well but not like I can shoot my 30-06 or my 243. I just don' t like the recoil of the big magnums. In fact I have mostly used my 243 over the last few years. If I buy another rifle in the near future it will probably be one that falls somewhere in between the 243 and the 30-06 like a 260 rem or a 7mm-08.