Hi,
Here is an issue i had with my Fenix 5X Plus watch :
The Wrist Heart Rate worked fine for about ten days, and suddenly, one day, when i tried to reactivate it (after i got my watch off for sleeping or shower or else), the heart rate measurement would need a very long time to be displayed, or would not be displayed at all.
The screen just read "Measuring" and nothing happened.
I tried several things, like powering off and on, same issue, reseting the watch, same issue.
I contacted the support and did a special reset that did not solve this issue.
I was able to exchange my watch and i could not believe my eyes when the exact same issue happened straight out of the box.
So i came back to the store and tested with the vendor some other models, another 5X Plus and a 5 Plus.
It was the same.
The heart rate needed about one minute or more to display, or was not displayed at all.
As a comparison, i have had a Forerunner 935 for quite a long time, and i never ever experienced anything like that.
The heart rate is displayed in a matter of seconds on the Forerunner, and about ten times this amount on the 5X Plus, if it is even displayed.
I reckon that most users do not even bother to deactivate the heart rate and that it probably explains why nobody brought up that subject yet, but heart rate measurement is one of the essential features of this watch, and at such a price tag, one would expect at least the same quality than most basic watch models.
Rest assured that i am quite a fan of Garmin brand and products and that i would really like to be able to enjoy their latest high end watches, but not if they do not provide the level of quality that customers are entitled to.
I hope that this post will be useful, and that this issue will soon be resolved for the greater good.