Love my Fenix 5 Sapphire! Wore it through the last 3 deployments I did. I can only remember it shutting off once due to overheating while running the base loop. It would still record data but screen went into survival mode in the hottest part of the summer in the direct sunlight.
I use it with all the apps I have for golfing, mountain-biking, running, and hiking. I really like the heartbeat monitor and the Garmin connect app on the phone. I can track my sleep and it helps me figure out how to get better sleep, at the same time it can log your stress patterns. So i can try to take lunch around those high times and lower any stress or work issues I am having.
Pretty cool that you can change the face into really anything you want, any style, you can add your own pictures to the image.
When this one dies (if ever), I will buy another. Get the Sapphire glass upgrade, it'll help to not scratch it as much. Crashing on a bike over and over is my biggest reason for needing the more resistant type.
Forgot to mention the straps switch out immediate and is an awesome feature. I have metal link for going to nice places or a leather one, and I have the rubber one for all the activities.