I actually flew Aeromexico both ways (I don't think there is another option for this flight). I live in Oaxaca and have to change planes in Mexico City when I travel to the US West Coast. The little commuter flight from Oaxaca to CDMX is okay, but on the longer flight the food is awful (does anyone know any airline that serves good food these days?), and the bottled water they offer is basically purified tap water (they could at least use one of the better spring water brands. Aeromexico isn't terrible (except the food); it's just 'average.' There is a variety of entertainment, but I guess I'm just 'picky.' I have more issues with the Mexico City airport itself than I do with the individual airlines.