Are people really planning on offering substitute check return? We are not in a state that mandates check return (thankfully) and we plan on only offering imaged checks, thereby avoiding the expedited recredit provisions. Is anyone else doing this?

There are many banks, including the largest in the US, that have many customers still requiring their checks be returned. If a banks wants to participate in image exchange and be a receiver, they will have to address that subset of their customers. One of the alternatives is to create substitute checks for check return. Not an ideal situation. It all boils down to the business value.