I'd stay away from Harvin. Tough matchup and new QB. I'm not fond of any of them, but Thomas has the best matchup. Mason's been more consistent (which isn't saying much) and his matchup isn't too bad. It's a dice roll, IMHO, but I'd probably start Mason.
Help with mine?viewtopic.php?f=19&t=489342
12 team, H2H, Standard Scoring (Starters in bold)
QB: P. Manning, Luck
WR: Julio Jones, Welker, Alexander, Hilton, Shorts
RB: Rice, Wilson, BJGE, LeShoure
DEF: DET, SD