Benfica had a very impressive group stage. I think that it was a huge achievement for them to finish the group ahead of PSG by not even losing to them for once. This is showing how much willing they are to be successful in the Champions League now. They lost Nunez to Liverpool while he was like a goal machine. But this still didn't affect them badly at all. They should be eliminating Club Brugge nicely as well.
We know how insane Napoli are this season. They are just incredible not only here but also in the Serie A. Not every team can keep two important tournaments balanced. But Napoli are good at it now. They finished a group with Liverpool and Ajax as the leader. Now they have got the most comfortable matchup compared to the other teams. Frankfurt don't have much experience here. Unless Napoli lose their focus Frankfurt isn't a big obstacle.