Only down fall to the .300 Win Mag is cost of ammunition. I am a WSM fan big time, everything I own. The 270 wsm is one heck of a caliber, just a bit light for some of the larger game. So I would have to say the most versatile caliber is the 7wsm, a step down from the cannon. But just like everything else in the hunting world, from shoes, jackets, sleeping bags to guns. It's only time before you realize that one is not enough. You just about have to have a couple items for different scenarios. So pick what you want to hunt the most and go with that first. Then over the years you will want to pick up something on the other end of the spectrum.