should i Map thecommon RFC Model to component contrl or custom controller?

In my webDynpro project , I have two modules one is DirectCustomer and InDirectCustomer. so i have set of RFS's in a single RFC model. In this RFS's some are common to both the modules. some are independent to each other. so i have created two controller component one for each module.Then i mapped the independent RFC'c to each controller seperately. But now the RFC's which are common to both modules to map, Better, should i map to existing Componentcontroller or should i create new customcontroller (like commoncontroller).

which i option is better, can u suggest me. I feel that, The common RFC's will be mapped to component controller, bcz it the Base controller for the both customcontroller , indrectly to the viewcontroller.

Can any body give me the suggestion on this