Another vote for LAN, especially if you can get the planes with the built in entertainment system in the seat in front of you.

Regardless which way you go, avoid American Airlines, best bet will be LAN then Mexicana.

Don't forget Air Canada/AC. Their entertainment system is very good, and Toronto/YYZ is an easy airport to connect in (at least on the way there).

I agree, LAN is very good.... clean newish planes, friendly FAs. However, last year the 767 MIA-EZE-MIA did not have the built in entertainment system in the seat. The 767 MIA-SCL-MIA was equipped with the built in entertainment system in the seat.
TAM is OK too. Nice Airbus a 330 ... but you have to change planes in Sao Paulo .. no big deal, you stay airside, no immigration.

Has anyone flown CO to EZE? I've flown CO in transcons before and had a good experience with them. I'm now thinking of going to Buenos Aires as well and wondering if CO's the way to go.

I've flown CO TATL and not enjoyed it every time. What is the A/C? If it's a 757, turn and run away.

I have flown CO to EZE and it is a 767, a bit far for a 757. Good service, probably the best choice of the US flag carriers serving EZE.

SAM

Good to know. Thanks for the info!

Have you also considered Delta ?

Being in Chicago, I'd go for:

/ best connection times
/ less flight time
/ space

If you are a Premiere Exec in UA, go for it. It's fine. You also get 50% extra miles so you will get 10,000 for the miles flown + 50% bonus, 15,000 miles, not bad.
Are fares THAT bad? I just did EZE/IAD/DXB/IAD/EZE for USD 1500 in W Class.

I recently flew YYZ-EZE-YYZ in AC 767s and was surprised at the large number of US citizens on the flights. Didn't realize that some of the US airlines may have poor service.
The AC is an overnight flight and the Business Class (they call Executive First) sections have those new little individual cubbies. Even the folks in the back get dinner, breakfast, wine and drinks. All seats have indiviudual AVOD touch-screen units which include a MAP feature.

Worth a look if you are close enough to use YYZ.

Commander Bob

I wouldn't be surprised at all. For *A people, we have 2 choices - via IAD on UA or via YYZ on AC. That is it. And from the west coast, it doesn't matter much, except I think I'll prefer the YYZ connection on the return, and the AC front cabin over the UA middle cabin. I'm trying it for the first time in July. In the meantime, all my other trips over the past few years have been on LAN, as will be my next trip in March. I just can't see any of the US carriers being any better, and I'd rather get out of the US as soon as possible than suffer the elegance of domestic UA, CO, DL, AA to IAD/IAH/ATL/MIA/DFW, even in the front cabina.

Just anecdotal, but we took Continental down and back in January and February 2009 and I was fairly pleased with their coach product. Both flights (767s) were practically full, but the planes were clean, the in-seat entertainment systems fairly good (movies, music, games, etc), the cabin crew efficient and hard-working, and the food at least a bit above average. Drinks did cost five dollars.

My sister came down on Delta to stay with us, and wasn't very pleased with her flight, although the only specific complaint I remember from her was the food.