Check with some bullet manufactures. The 1:12 twist rate may be a compromise, a little slow for the larger 250 grain bullets, but better for the lighter 158 grain bullets. One advantage of the 350 is bullet choices, you have many. However think about what you will hunt and the bullet weights you will hunt with. I bet you will find the bigger bullets are what you will want to hunt with. Therefore a faster twist may serve you better.
longwalker