Should I start Marc Bulger against the 49ers or Brady Quinn against Buffalo?

I know bulger is having a down year but Kurt warner just had a 300 yard ping effort and 3 touchdown effort against the 49ers. Its not like he's a chump either dudes been to pro bowls and has a huge contract so i wonder how bad he could really do. And brady quinn well he has had one start and i dont fully trust him.