I have a McMillian 300 WM and shoot 168 VLD's. They group about 1/2" in my rifle. I too, was wondering at first which bullet would be best. I called Berger Bullets and they put me in touch with Walt Berger, himself. Walt not only suggested the 168 VLD, but also sent me load data. He was a great source of info! If I were you, I would call Berger Bullets.
However, having said that, I also shoot the 180 TSX and my rifle groups about 3/4'', sometimes slightly better.
I use RL-22 for both loads, with very good results!
In my humble opinion, you can do very well with either