Good choice getting the 520; its basically a better Edge 500, which is, arguably, one of the best dedicated GPS options available for cycling. The bonus with the 520/500's reasonable size is that you can get a garmin wrist strap and wear it for running and whatnot. The only downside is that you don't get to view your running pace in min/mi, but instead mph or kph. Additionally, if you haven't already done so, check out dcrainmaker for some of the best data you're going to find regarding these devices. Regarding the general category of "wearables" for daily fitness... honestly, you might just want to pass on those. IMO they lack the usefulness I would want out of something I would wear daily; they're in their infancy and very much lackluster at this time.