There is no airline in existence with which someone hasn't had a bad experience. Since AA is huge as airlines go, it probably will have (by count) more travelers who have had bad experiences than most other airlines. People who have had bad experiences tend to post about them much more than people who have had good ones. You can read negative things about any other airline too. (My informal sense of the overall tone of FT posts is that UA tends to get more complaints than average, DL fewer, with AA between them - but they all fall within the same bell curve.)

Bottom line: I can think of no reason to avoid AA if it has the best fares and schedules to BZE - or anywhere else you want to go in the future.