Cuban Fibreless are heavy feeders so if your tree is not bearing, put on 5-6 handfuls of soluble zinc twice a year and the fruit will then hold on the tree.
Annona muricata We haven’t had much luck with grafted ones. The Puerto Rican one is doing OK but unlike Custard Apples it has to be ripe whilst still on the tree. You can’t pick it green so it’s not ideal for marketing as it doesn’t have a long shelf life but we sell a lot here. It can go a bit jelly inside when it’s too ripe. I like a squeeze of lemon over them. There’s quite a variation among them. They have a different skin. The smoother skin one is mucosa, the bareba is a white flesh. Most of these will bear fruit in the autumn but a few will hang through to winter but if you try and eat this fruit at the end of winter, they taste yucky – no flavour, but once the sap starts flowing, then the taste comes back. Ref: Bob Brinsmead - Tropical Fruit World