Many Mocambos/Patashtes are inferior, and/or picked too green and can be rather bad.
However, I have had several that were so good I compared them with Pawpaw, Durian, White-Sapote, and Cawesh!
Cupu-assu are not for eating out of hand--- they remove enamel, or at least it feels that way. But for jams and candies, there is nothing better.