Workbench Request vs Customizing Request
Workbench (ABAP Dev) transport request is client independent when you import it into one system it reflects it in all client in the same system, whereas the Customized transport request has to import in all client, actually it is client dependent request.
Work banch request is are client dependent,Workbanch request are user created object like ABAP report. When you transport workbanch request it will effect to perticular client.
Customize request are system generated or created by roles.when you transport custmize request the changes is effected to all client in the system.