Pac-Nor suggested a 1:9 twist when I was shopping for a .243 Win barrel. It works fine for everything, so far, but I haven't shot long bullets, except for Barnes 85 gr. TSX and Hornady GMX 80 gr. bullets, which are about long as 100 gr Sierra SPBTs (and shoot very well).
If I can't be with the rifle I love, I love the rifle I'm with!!