I have found V/B (and the associated FPA) to be both an excellent cross-check to VNAV Path as well as a stand alone tool for visual approaches. As we all know, VNAV Path can sometimes lead one down the garden path. With the runway line selected and entered in V/B, there is always an accurate picture of descent angle required to make the runway and current aircraft descent path. For reference, read Bill Bulfer's book on the Smiths FMC - some excellent and creative ways to make more use of all the toys.
Cheers