I have both 1/9 & 1/8 twist. with bullets up to the 143gr ELDX I can tell no difference in accuracy. Stellar accuracy from 100gr , 120 TSX, 130gr TSX, 143gr ELDx. Virtually the same load in either twist. If I were going to put a new rifle together I would suggest 1/8. Just in case you want to use one of the new 150gr class bullest. For me I see no need for those extra heavy bullets. 100gr TTSX for deer, 120 or 130gr TSX for elk . That has covered every thing for me.
