I agree that you have to clarify from where you are flying. I have been twice to South America and both times I flew AM
non-stop to GRU
and my overall opinion is a very positive one... not the best of the best (like CX
or something), but pretty solid. Within Brazil, I flew JJ
and I was impressed with their service... I am really eager to fly JJ
long-haul one day soon.
I have heard that LA
is truly outstanding, and that MX
flight is also great.
On the other hand, if it is a good fare what you are looking for, CM
may be your best options among the major carriers.
Ultimately, I think your decision should be determined by schedules, fares, connecting times (if non-stops are not available) and other factors such as whether your chosen airlines will give you miles.
Next flights: MEX-LAX AM 738, LAX-PVG DL 77L, SHA-PEK CA 789, PEK-PVG CA A332, PVG-ORD MU 77W, ORD-MEX AM 738