Hay Coug - I dunno. I prefer the 180 grainer in all my 30 bores, whether 08, 06, or the various European calibers I've loaded and shot. I feel the 150s move too fast and result in a lot of tissue (meat) damage. I have also seen 150s fail to penetrate properly after impacting bone, or spread bullet fragments throughout.
Lots of folk talk up the 165s - halfway between the 150 and the 180. You can load the 180 in the 06 up pretty hot, and it is good enough for just about anything you can hit with it. With the 308, you can also hot-rod the 180s but in one remington I had, the only 180 that would shoot accurately was a slow moving accuracy load. Even so, it penetrated far better than any of the 150s I've used and did not result in a lot of tissue damage or lost harvest. In fact, you could eat right up to the hole as they used to say.
Just my 2 cents worth. Mikey.