I wouldn't switch to AA for the food. Although I had some very nice salmon in F today on AA ORD-SJC (and an ice cream sundae), on two other recent occasions I've had meals I have not cared for (some type of tortellini in gravy that I will never order again, and canneloni that was more of a soup than pasta dish).

UA wins when it comes to point to point mileage, as AA charges per segment. On the other hand, AA has more F seats on domestic (the 737-800 I was on today had 20 seats in F, and I had an empty one next to me).

There's pros and cons for either carrier. It might come down to looking at whose route structure works best for you.