Performance wise,the 300wsm and 300wm are almost identical using factory loads.If you handload the 300wm offers slightly more velocity.If you handload you could just as easily flip a coin to decide but if you use factory loads,there is a much greater selection of loads available for the 300wm.As far as rifle weight is concerned,I carry a 300ultramag that weighs right around 8 lbs while elk huntingand I don't find it to be a problem to carry it all day.The extra weight also helps to absorb recoil and will make the gun much more pleasant to shoot.I do however prefer stainless synthetic rifles as the hunting conditions in the mountains can be quite severe and the less maintenance that is required at the end of the day,the better.The synthetic stock is also more stable in wet conditions that are very common in mountain hunting.