Definitely go with a 7 Rem Mag over the WSM or SAUM. Brass is easier to find and if properly built, you will get more performance with the 7RM over the others. If he doesn't mind a wildcat, my 7mm Rogue is also performing very well. 180's at 3100 in a 26" barrel is pretty standard with a mild load. Making them light and still wanting maximum accuracy is a balancing act.