those top two are 2 of my 3 keepers this year.
my league's scoring is different than yours, i'd imagine. ours combines carries, yards, catches and rec. yards for two backs and puts those numbers against your opponent's two backs.
so, for my league, jackson is a beast. and grant was a fantastic pickup for me. i traded him in mid-season for larry johnson (other players were involved on both sides).
i watched a lot of grant this year. that team is young and grant is a really, really good back who scores. gets a fair share of screens, too. but nothing like addai gets. addai won't get the consistent carries like grant or jackson.
the rams are switching offensive coordinators, so that could factor into it.
if it's valero, i know he likes to run.