You cannot even compare them as LAN is by far much better on all accounts.
I have just travelled to the USA in AA and returned on LAN.In AA one travels in older planes with no private entertainment and lowsy food service and expensive drinks. With LAN one flies a modern plane with private entertainment and free drinks and much better food. Their land services as well are much better.
And to try to compare them for local services is even worse. With AA we travelled on a 1986 plane ! No food services and expensive drinks plus a charge of $25 for each check on bag which by the way did not arrived to my hotel until 8 hours later.
So, when travelling to Peru I strongly recommend you use either LAN or TACA for a better service and on top, low prices on their local flights, its a no brainer.Edited: 29 June 2011, 17:35