Haven't flown on these very much but don't hear good things. Has anyone had good luck on either airline lately??

I have flown exclusively American since United dropped "my route" several years ago. I have no complaints.

Much too broad a question. Where to where, when to when, coach or business/first?

January from Bhm to SJD( los Cabos) coach

I realize that the plural of anecdote is not data but here's my experience:
I had a huge battle with AA in the early 1990's and vowed to never again fly them. Did not for 20 years or more.

After the AA fight became a CO loyalist. In the months after the merger with UA things got so bad that I decided to take advantage (no pun intended) of AA's status match offer. First flight as top tier elite was nice. Scheduled a European trip just to meet the status match requirements. That international flight was dismaying (nasty old plane.) Subsequent flights were a mixed bag. At end of year they claimed some fine print disallowed credit for some miles so denied renewal of elite status. Deja vu all over again.

Decided to give UA another try. They have made great progress. Planes are much cleaner and more comfortable than AA, staff both on the ground and in the air are much friendlier. Staying with UA for now.
Have heard similar from fellow road warriors.

Our ff plan is thru UA and we use it for partner carrier flights to Asia with usually ANA and Asiana amd Thai once so in that regard it's great. We fly UAL for USA flights and though they have a long way to go to compare to Asian carriers and probably will never reach that level, at least for on board service they have improved since we, like Seamus wrote them off for terrible service. The new CEO for UAL wants to improve their product. I hope his recent heart transplant won't hinder him. Let's see.

Both AA and UA will use small regional jets on one or more of the legs, or maybe 737s on the flight to SJD. All will be equally (un)comfortable. If frequent flyer miles aren't a concern, I'd go on the best price/schedule mix for your needs. You'll likely change planes in Houston (UA) or Dallas (AA) en route, although both will probably offer Chicago connections, which I wouldn't take in January for obvious reasons.

We recently had good flights with AA to and from Asia. It the airline that offers the most options feom my home airport. I was a loyal United flyer umtil every domestic flight they pit me on was a fejional jet. No fun.

Thanks. Flight connection is through DFW or HOU. May return on Delta since I have miles. Delta going out only has 56 minute layover in ATL- glad to hear someone has had good luck with AA and UA!!

Your suggestion of buying a one-way ticket for part of your itinerary will need careful research, since trans-Atlantic one-ways can sometimes cost nearly as much as a round trip. Makes no sense? Right -- but there it is.

A year ago, I would have said American was better than United. But I have flown United a fair bit over the past few months (enough to get elite status) and while not exactly impressed (aside from one instance where multiple people went above and beyond), they have been competent. I would not hesitate to book them if the price and schedule worked.

American... I don't know what to say with them. I think the product that they want to offer, and which American was working towards before the merger, is the right direction and has promise. However, I find the legacy US Air domestic fleet to be uncomfortable and the risk that you'd end up on one of their planes makes me hesitate to book American.

Neither American nor United are at Delta's level. They run an amazing operation and would be my first choice on any route where the schedule and price are competitive. Personally, I would even book them with the 56-minute layover in Atlanta, trusting in their reliability (and schedule padding) to see me make the connection.

I have only flown United recently and have not had any issues. 2 out of the 4 flights in the last few months were delayed only by 15 minutes.

Cabin crew were pleasant and professional.

Just remember problems can occur on any airline at any time and flying in general is not always pleasant. If you haven't flown in a long time, go the best routes and prices and take it from there.

Everyone has different experiences, but my experience has been horrible with AA. Almost always horribly late. Have had pretty good experiences with UA.

I am following this because I have flown almost exclusively AA for years, because the route/flight times worked so well for us, which racked up some useful mileage. However, we just booked LHR-IAH on UA for Christmas because the price and schedule were so much better than what AA had available. If UA impresses, I will have no problem leaving AA behind.