Don't disagree about Pats RBs in general, but Lewis seems to be the guy there, has been consistent with fantasy pts thus far, and is rated to be pretty good the rest of the year from the fantasy nerds.
One reason he probably hasn't auto accepted for Sanders is that Peyton isn't anywhere near what he's been and is the lowest rated starting QB in the league right now...and the weather is only going to get worse as the season goes on.