Hi Everyone,
Thanks for the welcome and your feedback. I've been traveling and just realized I had notifications off so I didn't see your comments until now. To answer some of your questions:
I don't know how long I'll be living near PMC. It could be a couple of years or it could be permanent.
My interest in a ffp is international upgrades and miles. I basically don't sleep at all in economy so since my travel is for work I try to travel in business to get a few winks before walking into meetings. I pay for it when the price is reasonable, otherwise I try to use upgrades. All of my travel is out of Chile, but a good amount is domestic in the US. But I don't care all that much about domestic upgrades. I have a family of 6 so I rack up miles from business travel to use for personal international travel for my family. Lounge access is nice, but I almost always have access to a lounge through Priority Pass or otherwise so I wouldn't go out of my way to have more lounge access.
But I just realized an important factor. A lot of my clients are government-funded non-profit organizations. To get reimbursed for travel with them I have to be on US flag carriers (or codeshared partners) due to the Fly America Act. So that basically eliminates LATAM as a reasonable option. Really my choice is to stick with United or jump to AA. I'm not considering Delta because they also don't serve PMC and between UA and Delta I would stick with UA. So really this is just a question of whether AA is worth the switch.
If Star Alliance served PMC and had better routes from South America to Asia and Europe I would stay put. Because apples to apples I consider Mileage Plus to be a better program. At least for the moment. I'll give it some more thought and make a decision by the end of the year.
Thanks again for your feedback.