Performance and simplicity of client code come to mind. If the API is consumed by a UI, it sounds good, particularly if the API provide hypermedia controls that can help generating the UI. But for automated consumption, issuing one call to a know endpoint still seems so much more straightforward than walking down the links graph until the expected link relation is found. I guess I just have to go & try by myself because at this point it seems we don't have much documented experience to rely on.