Achachairu has a very nice texture and the flavor is good, but not exceptional, like with mangosteen. Biggest downfall is very big seed in a small fruit. I think it could make it to world wide markets and be in same caliber of quality with fruits like kiwi, feijoa, tamarillo. Don't think it's in same caliber with top notch fruits.
Note that in videos they say it's a tropical fruit, but i think it's a subtropical as it grows in high elevation foothills of Andes (Santa Cruz, Bolivia). It is adapatable to lowlands though, as the fact that it's being grown in Queensland shows. But it could certainly be grown in cooler parts of Australia as well. Note that fields in Queenslands of these trees are all in full sun, not partial shade like some literature recommends.