IMO if I were to get a new rifle and didn't have either chambering, I would go with the 300 WSM. I like the 300 WM but the WSM come mighty close to it ballistically. The short fat case of the WSM in theory is more efficient and I haven't seen a rifle yet in this chambering that didn't shoot well. As for the 308, I had a couple and shot game with them. But the round simply does not impress me at all.