This debate as to which is better between the '06 and the 270 has been going on for decades.And the 270WSM is very close to the 270 Win.But to keep within the topic of this post and as much as I like my 270 - if you are going to have only one rifle and your choice is between these 2 chamberings, I would have to suggest the'06. The versitility has to go with the '06. There are simply more choices in bullet weights and a bullet in the 165 - 180 gr. will take anything in NA. Although it wouldn't be my first choice for big bears.