I don't fly AA. Flew UA for first time a few weeks ago so I won't comment due to sample size. I had 75K equivalent on AS/DL so factor that into my list. Lots of western Canada short hauls and transcons:

- Knowledgeable AS/DL phone lines and extremely swift resolutions. Hardly had to wait even during pandemic.
- Need to call a separate line for Aeroplan related problems.
- No bugs with online wallet systems. Need to call in/write if money is not deposited in AC wallet. AC app is bad generally.
- AC segments go missing. Need to call in/write. Don't understand why these things aren't handled proactively
- Very limited SDC privileges from AC; very flexible, generous, and easy from AS/DL.
- Need to call in to cancel AC flights last minute (can't do it online < 2 hrs).
- Short hauls that actually have preferred seats. Only diff for AC is that you are at the front.
- Cancellation fees that would not exist but for competition. I get hit with GST on "cancellation service charge" or whatever it's called.
- Forced by buy Flex for 100% SQM (unless you don't care for this I guess). "Standard" is really misleading. This makes flights more difficult to search and compare on Google Flights. My general expectation is that a "standard / Main / nonbudget" fares should equal 100% SQM.
- Duopoly pricing in Canada. Maybe this is a country thing rather than an airline thing.
- Constantly delayed flights.
- Constantly late bags.
- AS/DL serve edible food. Can't tell the difference between AC econ/PE/biz food except the plating (at least from my experience).
- Sloppy and apathetic handling of APPR issues on top of constant delays and cancellations. A lot of time is wasted b/c AC's go to move is to deny compensation requests. WS is so much better on this . Some of my claims are approaching 2 years old and may become barred for legal action in some provinces like BC.
- AC not proactive on service related issues eg. Gate Gourmet strikes. Do I really have to justify/beg that I need compensation for no food on business flights?
- Lounges are much nicer. Overcrowding is a general issue and not pertinent to AC.
- Non-econ hard products are much better eg. Ragged and old bedding is not used in lie-flat biz
- You may or may not be able to predict if you are going to get eupgraded based on the Seat Map which is not accurate in the first place so why have this map in the first place?
- I get thrown into odd situations in IRROPS once in a while. Got told that I need to retrieve and check-in my luggage again once at YYZ for a new domestic flight. Even I knew that this would be impossible. Shows lack of knowledge from the ground crew
- Another IT issue: can't connect to AC wifi sometimes.
- I don't understand things like having to activate AC Wifi benefits on a flight and sometimes you may not be able to do it b/c you can't even log in.

Generally feels like AC is years behind what should be the "standard" for airline operations. Ac wallet just came into play last year. AC feels plagued with IT issues. I do not feel an urgency to provide good service from AC.

Oh and I can't wait to try these so called so called top ranked business flights from Lufthansa, ANA, Emirates, so forth. I'm still newer at this game, but I'm very convinced that there are much better offerings from other airlines from all over the world. I'm very disappointed in Canada's de facto monopoly/duopoly airline given the market share in a lot of aspects and the problems seem to stem from general apathy. It's not like AC is broke or anything. AC does have some decent things like being able to stay at the 75K level to share elite benefits (other airlines such as AS needs 100K) and the AC Cafe, but there are too many problems that make my flight experience overly burdensome.