I think Boren and Stoney have the best shot to make a roster because of their versatility.
Boren can be your starting FB (assuming you have need for one), an emergency linebacker and a full-time special teams guy... coverage and protect. When it comes to undrafted guys, versatility is a big deal.
Tressel's commitment to special teams has really helped some of the low-level NFL players stick on rosters. If Brandon Saine couldn't cover punts, he certainly wouldn't be on the Packers (assuming they bring him to camp again). Boom Herron made an impact on punt-block for Cincinnatti, Posey had a special teams TD for Houston. NFL coaches love guys that can save them roster spots by knowing more than their one position.