Just my opinion, but I think the Raiders are a lot better than people think. I'm not saying they're going to win the Super Bowl or anything, but they're no worse than an average team IMO. If you take out their first game of the season, they've played very well. They beat up on KC on the road and they should have won last week on the road at Buffalo (who is everyone's favorite 'sleeper' team this year).
If they had won that Buffalo game last week they would have been 2-1 going into this game, and I guarantee you SD would have been laying -3 at the most. But because they lost people just focused on the fact that they lost and everyone assumed Buffalo had a letdown. It's funny how a few plays can completely shift the public, and Vegas', perception about a team.
GL