Pros of CX:

-Outstanding 5-star service as always
-Lie-flat seats if you want to sleep for the duration of the flight
-If not, watch a quick show or two on CX's AVOD system, StudioCX
-Award winning lounges
-It's a 747!
-The hour of arrival is not that late

-Cons of CX:

-Could be swapped for a regional configured aircaft last minute
-You arrive at Terminal 1 which is always a zoo during late hours

Have never been on PR so I can't really comment but I fly in and out of MNL on a regular basis.