Eh that's a tough one. I would lean towards Spiller, he had a 100 less carriers than Lynch and only socred 35 less points in ESPN standard scoring which I think is non ppr. I would lean towards Spiller because I think they are going to run the ball more and get Spiller more looks to be explosive while Seattle tries to let Russell Wilson open but that might keep Lynch fresher. I don't think there's wrong answer
In a non-ppr I'm taking Lynch. Seattle's O-Line if healthy is going to be ridiculous and Spiller lost his Pro Bowl Guard in Levitre this offseason. If this was PPR I'd be taking Spiller just because he's prob going to catch 60+ balls.