I have owned and taken game with 300 RUM, 300 Win Mag, 300Weatherby. They all do an excellent job. Sold them all and bought a Win Model 70, SS in 300 WSM. It also kills elk cleanly, and is more than enough for anything else I hunt. One is as good as the other. Some just kick a little more, make a little more noise, and push the bullet a little faster. I doubt the dead animal can tell the difference. Truth be told, it's the person behind the gun far more than the gun/caliber. You should be quite pleased with any of them.
Good Hunting,
Hal