Adam,
I chose the biggest fruits and they were kind of round for these photos, in Recife. The original achachairu seeds were from Santa Cruz, Bolivia. My friend imported the seeds long time ago and now he grows them commercially.
He calls achachairu, "garcinia laterifolia". We have had our share of controversy naming garcinias.
Tomas, I tried to locate the guy you mentioned is grafting achachairu to a native Brazilian garcinia. I have read that he is having success with them. Apparently, the grafted achachairus produce in three (3) to four (4) years. This guy is located in the state of Goias. So far, I have not been able to talk to him.
My original post, I meant to say that garcinias do not do well when grafted. That was one of my first statements.