In the Google groups archives in rec.guns, one can do a search for posts by Bart Bobbitt over the last 20 years. He was a serious competitor for many years at Camp Perry high power with the 308. He is good at describing what he has learned.
He seems to favor IMR4895 up to 160 gr and IMR4064 over 160 gr and IMR4350 at ~ 200 gr.
For a long time my go to load in my .308 Win was a CCI 200 primer and 46.0 grains of varget behind a 150 grain Sierra Gameking. I shoot a 26" barrel. But the .308 is not a picky cartridge. Lots of powder will work well in it.
I tried the Benchmark out today and it seems like it was a good choice. I used 41 grains with Winchester brass at 2.750 overall length. It looks like it's going to be sub half inch. I pulled off on my last shot so I won't know for sure how accurate it's going to be till tomorrow but things are looking very promising and this is the first load I have tried in my rifle.