Bangkok yes 500g to 1kg are large examples of the top types.Low latex,few seeds (one or 2),strong caramel and even vanilla taste,low bruising and staining of flesh and spherical shape are the hallmarks of the best abiu.
Z2,Z4,Inca Gold,Gray,T35,E4 and Cape Gold (as well as Marissa apparently) are some of the types that make the grade. Lot latex and no proness to flesh staining and bruising are the first qualities to look for.Firm flesh rather than jelly and a taste that pushes through the caramel into other tastes and is sweet is what to look for.
I am yet to see pictures of top abiu from south america and think some good ones must exist in their homelands.