The Saints have an excellent defense with tremendous depth. It's their offense, though, that gets most of the attention. New Orleans' offense, however, isn't going to be as good as Michael Thomas is out with a high ankle sprain. There's a huge drop from Thomas, maybe the best wide receiver in the NFL, to the rest of the Saints' wideouts. 
The Raiders' defense is young, but has potential. It's a better unit now that underrated safety and sparkplug Jonathan Abram is healthy. He had 13 tackles in Week 1.
The Saints should be able to keep Derek Carr and Las Vegas' offense in check. Carr is more game manager than gunslinger having reached 300 yards passing just once in his last 20 starts. The Saints' defensive coordinator is Dennis Allen, who is familiar with Carr having been the Raiders' head coach from 2012-2014.