I would keep using Strava even if I weren't training... for a few years I didn't bother downloading the files from my 705... then it eventually crashed and I lost all that data.

When i started riding again last year, I uploaded all my old files to garmin and strava... and now I find myself really missing those files from 2-3 years of riding that I lost. I sometimes want to refer to some of those rides/data, but they are gone forever.

The 520 I got to replace the 705 seems the best balance. Just GPS and data recording, small (enough), battery lasts long enough (at least double the 705, never an issue on any single ride, even an all day affair)... but the real key to me is the "auto upload" to garmin -> strava. I never lose ride data because it goes automatically (and the 5 times in 100 it doesn't I can easily trigger it wireless without having to plug it in to the computer).

While I may or may not care about any single ride now, who can say what my priorities will be next year? Having the data for future reference (at almost zero incremental cost/effort) is one of those things I've learned has a value I can't really estimate today.

And tomorrow, when I suddenly realize the value? It will be too late to record the data!!