It hasn't been explicitly stated, but there are lots of people that run a V2 or V3 (or any other preamp, for that matter) directly into the line-in jack on a handheld digital recorder. That's a perfectly fine rig to use and, in the end, would sound every bit as good as the recordings made with the 7xx as the recorder.
Of course, the V3 can also output a digital signal, so a D50 for example could be used as a bitbucket. (I would add that, I would question anyone that claims they can choose in a blind test the sound of the ADC of the 7xx over the ADC of a handheld.)
That said, I do understand people that use the 7xx behind preamps because the 7xx is just a damn fine piece of gear and if I had the money, I'd use the 7xx in a heartbeat because it's just a joy to use high quality equipment that has a GREAT set of features (both hardware and software). A 7xx is ALOT more than just the pretty lights, but it's true that the lights are nice too!