Re: 308 question
In short, yes and yes.
The 150's you mention are suitable although I would not use the 150 sst for the very large mature WT or mature mulies. 150 Interbond, 150 accubond etc for the bigunns. That is however, only my opinion.
Long range shooting is a process that ends with a result. Once you start to focus on the result (how bad your last shot was, how big the group is going to be, what your buck will score, what your match score is, what place you are in...) then you loose the capacity to focus on the process.