WSM cost more to but and more to shot for ammo, than the traditionals. If you buy factory ammo (like said) you are very limited at this point and availablity is an issue as well. I don't believe they are better than their long action pals, i guess if your a short action guy and need less weight maybe a good choice.

I have used a 270 and several 30 cals for deer, all work well. However i have now gone to the 7 Rem Mag, I couldn't be happier and it is all i need for lopers-moose. Shells are cheaper and recoil is less than the 300 win Mag. But either would be a good choice.

Just buy what you want and you'll be happy. I know many tried to talk me into other calibers, but in the end I wanted the 7 Rem Mag cause of it's flat shooting, it provided me extra punch than the 270(I prefered to use on Whitetails), range of game I could take and bullet styles. I didn't ever use 200 Gr or up with my other 30 cals, so never saw the need to buy a 300 win just in case. Bonus was cheaper shells than the 300 win Mag!