SCL is a much better transit airport than EZE. In fact, I just transited SCL yesterday on the way to EZE

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The LA A340 reconfiguration hasn't yet started. The seats aren't bad, but they don't lie flat. One of the 5 planes does not have the AVOD system - the other 4 have an older, but not bad system. I've never flown trans-pacific on LA, but have probably 25+ longhaul north/south segments. Food is usually pretty good. Wines are very good. Service is variable, and usually very "formula." I've never flown QF.
SCL transit doesn't pay a fee.