The one area where the F5 has been a massive letdown is in connectivity to other devices - specifically Ant devices but it does also affect bluetooth connections. The hardware design is flawed and it's not something they'll ever be able to fix via software. I regularly lose the connection to my Garmin HRM strap when doing any exercise that sees my hand fully extended away from my body (e.g. Boxing, or most Crossfit style workouts). I also own Runscribe Plus footpods, and before the creator came up with an ingenious solution none of us F5 owners were able to keep stable connections to the pods. Nobody else had issues - Forerunner 935 owners and Fenix 5X owners had no issues, but every single F5 and F5S owner had problems staying connected.