I have booked my flights with AR as for where, when and how I want to plan my itinerary, LA simply does not work.
AR has a Visite Argentina offer:
http://www.aerolineas.com.ar/arg/mai...oma=en&id=1800
If you buy this Visite Argentina offer, your baggage allowance will be the same as your international flight. Otherwise, it's only 15kgs for regular economy.
At the end, I booked AR's Club Economy for about 15% more to "pamper" myself a little bit and also for the change flexibility and 30kgs baggage allowance.