I was just out today running my .308 test loads in my Savage 10 TAC. The 3-way Bullet Smackdown... SMK vs NCC vs Hornady 168's... the SMK walked away with it, again. It's just a better shooting bullet, period.
My powders were TAC and IMR4064. Those are the two powders I've picked, because IMR4064 works well with both the 168's, and, eventually, the 175's. TAC has impressed me with it's versatility and performance. In my tests today, at 150yds, the 168grn SMK shot equal with both of those powders... it was hard to tell the difference. I did not test for velocity... that's the next step.
ETA: I'm not sure what's wrong with the Hornady BTHP bullet... in the 6.5CM, the Hornady outshoots the 142grn SMK, but in two different sessions, the .308 SMK mopped the floor with the Hornady.