As mentioned above, buy the best glass you can afford.
Depending on what you are hunting, the environment you are hunting, and your chosen/preferred hunting style (spot and stalk vs stand hunting), choose the variable power range that best suits those conditions. E.g., a 3-9x40 or 3.5-10x40 for all around use across the widest variations, 2-7x33 for stand hunting or spot and stalk in the thick timber, or a 4-12x40/4.5-14x40 for open country/alpine hunting.
If you are stand hunting or in open country/alpine country, a range, dial, shoot set up with turrets can work, while spot and stalk or stand hunting in the thick timber is better suited to a plain duplex reticle, and for spot and stalk over a wide range of terrain and environment types, a reticle with a Bullet Drop Compensation (BDC) element may be more useful when range/dial/shoot may not be as convenient.
As I am of the latter group, I have a Leupold VX-3 3.5-10x40 B&C scope on my 300 WSM. Has worked great for me for the past 22 years! But this is just my preference.