When would they be ready to fruit? After 1 or 2 growing seasons post grafting?
Mostly depends on your skills as a gardener. I usually let my newly grafted avocado trees hold fruit the 2nd year but that's because they're on a well established, robust root system and the grafts/trunks have lignified by the second year. For example, I grafted four varieties and let 7 Sir Prize, 2 Holidays mature. The Ardith and Pinkerton fruit dropped.
IOW, your call. You have to learn how to balance the fruit load with the canopy and root mass no matter what fruit you're growing.