I will probably convert my ex-MRU AONE5 into an AONE6 (adding South America) later this year when I complete the first leg of the ticket.
Why? I like to go to South America in the winter time and fares are rarely less than $800 (and often around $1000) in Y. Adding the extra continent to my AONE5 will cost around $800, which is the same as a "cheap" coach ticket this time of year. Yeah, Lan losing F is a bummer, but by the time I would do this JAL will be an option (JFK-GRU) and AA will run F to GRU, GIG and EZE. Even if I opt to go on Lan in J it will still be a great deal.