I like that they are able assist in determining how much you can spend with your current budget as well give recommendations of what is needed vs not so important within an infrastructure upgrade project! The benefits have been many but one thing would be if we could see our actual ROI at any time during or after implementation which was difficult because it took too long from when work started until results were visible (and sometimes longer).
We used their expertise & experience w/rattans consulting throughout all phases including design / architecture reviews through deployment phase - very professional team who made us feel comfortable about being part ous business partner rather than just another client!!