More a LAN booking question than a LANpass question...

I'm going to be spending some time in Argentina in November, and want to include a side trip to Mendoza. In looking at the LAN USA site the round trip is in the flexible fare category only . However, if I book the same itinerary on LAN's Argentina site, the lowest fare available is less than half of what it is on the US site. ($206 v. $472). I found the situation similar on the sites for Aerolineas Argentinas.

Has anyone booked on the "cheaper" site and run into problems? I realize the lower fares come with restriction and may not earn miles, and that's fine for this part of the trip.

My issue is the distance is the same as SEA-SMF, and $472 seems steep for that length of a flight. I know this is comparing apples to oranges, because ANC-SCC is also about the same, and that flight runs nearly $900 in the cheap seats, but lets just say it is more than I am accustomed to paying.