As a rookie, the third-round pick Smith ran for nearly 1,000 yards and eight touchdowns, but injuries prevented him from building upon it. Smith actually looked good at times during his limited action last season, but the Lions obviously had other plans (Leshoure for instance). Smith did a nice job not burning bridges when the Lions didn't tender an offer and, assuming he's been working hard and staying hungry, could help him wind up back with the "big blue." The Lions continuing to work out running backs does make me wonder about the status of Jahvid Best, though.
As for Davis, he's a former first-round pick, a 6-foot-6, 355-pound mauling blocker, who started every game his last five seasons. It's no secret that the Lions need OL help wherever they can get it, so Davis could come aboard and make an immediate impact.
It'll be interesting to see if this picks up any steam and the Lions opt to bring either aboard.