While this thread is comparing the 300 WSM to the 30-06, a closer comparison would be the 300 WSM and the 300 WM. The WM is a little more powerful than the WSM, but not much. The WSM is much closer to the WM than it is to the 30-06. You might call it a WM Light. If you have experience with the WM, you pretty well know what the WSM will do.
Nicely said, I've been thinking the same thing lately and almost willing to give up my 300 win mag since getting my new wsm. It's (300wm) the only left hander in the stable though, so I'm conflicted as to whether or not I should get rid of it
