PSG vs. Real, Villarreal vs. Juve, Atletico vs. ManU are very unpredictable pairs, I'll wait a real rumble there...In each other pairs I can see a clear favorite, excluding, maybe, Benfica vs. Ajax.
The PSG Vs Real Madrid match will be an interesting match. The two teams are in good shape. PSG are leading in the Ligue 1 standings, while Real Madrid on the other hand are also leading in the La Liga standings. Is quite hard to predict who wins, but I think many goals will probably be scored. Atletico Madrid will have a tough match against Manchester United. Atletico Madrid have to play this match carefully to avoid losing, Because Manchester United focus are mainly on their Champion League matches. However, the Round 16 will indeed be very interesting, and I can't wait.
Real madrid I think will be seeded in this match because even though they are both top of the table in their respective league positions but on the other hand there is a stark difference in their performance in the UCL and even compared to their team I prefer to wait to see Sergio against his teammates first.
On the other hand, Athletico is again faced with a team in which there is Cristiano, it is very interesting how in some of the previous UCL matches they were always eliminated with a team in which there was Cristiano as a player.