Should i start Ben Roethlisberger vs. Car or Tim Tebow vs. Hou?

I"m wondering if i should start Big Ben at home (22 degrees snow flurries Thursday night) vs the Carolina Panthers (#8 p Def) or Tim Tebow at home (47 degrees Sunny) vs. the Houston Texans (worst p Def in league) for week 16. I'm worried the Pitt game will turn in to a run game given the weather and crappy Panthers run Def.