Originally Posted by hsuehhwa

If you like long rides (> 6 hrs), you're more likely to experience Garmin failure in your rides. My Garmin 520 crashed approximately once of every six century rides. That is, one Garmin failure every ~42 hrs of rides. For most, it's probably quite acceptable. For some that enjoy long rides/Century/Gran Fondo events, it could be troublesome, since you would like the events being recorded accurately. As a result, I've seen people using two devices to record their important rides. In addition to my Garmin 520, I always use Strava on my Apple Watch in the paid cycling events.