I am a cyclist, swimmer and occasional runner, never a triathlete. Also weights several times a week. Two activities every day. Some of my electronics are SRM, but the bulk are Garmin. Because of Garmin's anti-privacy document I will NOT allow any Garmin product near the internet.
Health data is big business... It was the primary revenue source for companies like Strava for many years and there is no doubt it is money for Garmin too.
I hate this. Something may start innocently, but in a horribly cynical and depressing way, imagine the absolute worst in humanity and how it has come to pass. Imagine the worst possible way health data could be misused.
I keep my data on the device until I upload it to my laptop where it is imported into Golden Cheetah.
GC is a much more powerful analysis toolkit than any of the online services and a real learning curve. The only thing you won't get from it is the endorphin hit when someone gives you a like.