Has anyone used the nutrition tracking?

I seem to be contrary to everyone else's request to turn of nutrition tracking on the edge 530. I haven't purchased one, but one of my biggest issues is always nutrition so having the ability to track and trend data within the garmin software rather than a notepad sounds very useful to me. However, not having the 530 yet, I'm curious if it's more of a log, or if any meaningful insight is graphed and can be ascertained from the garmin connect website. For instance, something like calories consumed vs average HR during a ride might be useful; I've been trying to max out grams on the longer rides, but how hard I work is directly correlated to how much I can consume...