Definitely the Sm/Md size. That way you won't have a huge binding where your boot will slip around, with an added bonus of being a bit lighter.
15 NS Ripsaw . 14 NS Proto HD . 14 NS Cobra . 13 Gnu Space Case EC2 . 2013 Salomon Pow Snake
14 Now Drive . 13 Now IPO
14 Flow Hylite