I've tried the whole gamut of bullets in my 20" rem 700 SPS 1:12, from 155 Scenars and Palma SMKs to 185 Bergers. THE most accurate bullet has been the 168 AMAX, followed closely by the 175 SMK and 178 AMAX. The 168 SMKs did fine at 500m and in, but I never bothered with them much since I wanted a single round that would be good out to 1K. I settled on the 175 SMK for great performance from 100-1000 yds. The 168 AMAX was a hammer at anything inside of 800 but seemed to open up a bit more than I cared for beyond while the 175/178s could hold on.
I REALLY tried to make the 155s Scenars work, but they just never shot well in my gun. I think my issue was I could never get them fast enough out of the short tube to make the lighter bullets work. Most folks are talking 2900+. I was lucky to get in the high 2700s to low 2800s before getting pressure signs. And accuracy was really poor compared to the heavier bullets. So I finally gave up on them. I think they are great out of a longer barrel where you can push them hard enough without overcooking your load.
The 185 Bergers were ok, but honestly I never saw any difference to justify the extra cost over the 175 SMKs.