Hi Swathi,
In our client we only used process instruction categories at control recipe destination. And assign this control recipe destination to master recipe. We only had 5,6 control recipe destinations with different process instruction categories for different input tables or functionalities. Flexibility is that using filters like work centers, item category in bom, sort strings, batch managed etc we can decide which process instruction category will flow into process orders and then to PI sheets. So data maintanence is less. But if you cannot control different proces instruction categories using filters and each master recipe needs different instruction categories then you need to maintain at master recipe level. You cannot maintain at both places as this may duplicate the instruction categories. If there is any way to differenciate both the materials like stock item and non stock item or maintain a sort string in the bom you can send different characteristics by maintaining PIC's at control recipe destination level.
Thanks
Rijil