I wouldn't go that far (and I'm EXP on AA and 1K on UA so I have quite a bit of experience with both ). Meals in F overall are better on AA. AA dumped the 762s domestically last month. The 77W is way ahead of anything UA has. Similar with the A321T. AA vs. UA 737NG or 757 is pretty much equally medicore. S80 is old but they are going away rapidly. The A319s suck equally from what I've seen (I've yet to get one on AA though), though I believe UA's have more extra legroom economy seats. The A320 is maybe slightly better than a 737, but with only 12 F instead of 16 F that puts it well behind from an upgrade perspective (read: higher chance of flying Y on an economy class ticket). And it isn't better if simply paying for F anyway. The 772, AA has SWUs if you are EXP, so you can usually upgrade an economy ticket into biz, or a biz ticket into F. AA 772 F > UA 772 J, and AA 772 J > UA 772 Y. And AA 772 F > UA 772 GF.

And don't try to tell me one of the 739ERs without TV or Wifi installed yet (which I had ANC-SEA-IAH recently enough, as well as BOS-IAH) are anything other than total garbage.