You won'y get much if any more thump with the 270 WSM over the 30-06. With bullets up to 165 grain, you will see no real difference between the 30-06 and the 308. The most versitile of the 3 for my money would be the 30-06. The 308 however with the 190 grain Hornady BTSP will take out anything in NA without any problem. This is a very underused bullet.