I have a Fenix 5 I use for running and occasionally record a bike ride. I use a 520 on the bike. If I'm using the watch I don't usually look at it so it's useless for navigation. I find the wrist HR is useless for running or cycling. It provides a general idea but is very slow to react and doesn't always go in the right direction with changes in intensity. I like the 520 for the bike. It's a decent size and has everything I need.