Originally Posted by virtualtroy
I suspect with that routing that it'll be a one (Y) class service operated by LAN Express, similar to the northern flight which terminates at La Paz, Bolivia.
That said, despite the sardine tin seating configuration, there seems little else to distinguish between Y and J service on LA.
What routes are you talking about, and how recently? I have flown LA within South America in J (EZE/SCL) and within Chile (SCL/PUQ) while they still had the 2 cabin service, and found, for the length of the flights, for the service to be very good.