I'm in nearly the same boat. I've got a .338 Edge shooting 300g Bergers but it weighs around 15lbs and simply isn't much fun to pack around in rough country (like the Wyoming elk hunt
I should be going on this fall). So, I'm building a light-er weight .280AI (Rem 721, Manners EH1, Bartlein #3 1-9 barrel) that I plan to be able to shoot out to about 600 yards on elk and/or deer.
My plan is to try the 168g Berger VLD's and the 180g Berger Hybrids as well as the 168 and 175g Accubond Long Range if I can get my hands on them. I like the idea of shooting either the 180 or 175's if the accuracy is there and I can push them fast enough.