Six of one, Half a dozen of another. You can't go wrong with either one. I like my 300 wsm quite well. Brass doesn't cost much more than 300 wm so for me the ammo cost argument means nothing. You might save a little weight with the WSM but you lose the ability to chase the lands and still use the Magazine. Recoil, accuracy, Kinetic energy, & ballistics are basically identical. Of course if you want to push the envelope with the 300 wm you can exceed the wsm by some 1-200 FPS. I prefer to go with the most accurate load not the fastest anyway.