From deer to moose, your range of prey is quite broad. If I were you I'd get two rifles, but if forced to choose one, I'd get the 300. I like to match the power of the rifle to the animal I'm after, while minimizing the recoil effect. If you're doing mostly deer hunting, with occasional elk, moose, bear, etc., you'll be unhappy while you're deer hunting with a .300 Mag.