HR sensor not accurate for intense exercise

I've found the Gen5 (& Gen4) to be line-on-line with an HRM-Pro for running and biking activities.

At hr in the 140 and 150 range I do as well. As soon as I get into the 160s, the wrist drops to the 140s

WHR is not reliable. For some it works, for others not. Independent of manufacturer. If you need activity based heart rate data there is no way around a strap or a optical sensor for the upper arm like the polar verity.

Based on what I've read from reviews, the new HR sensor in Fenix/Epix Pro models behaves mostly the same for running (I remember reading that it only uses the two center leds in most circumstances, just like the older sensor in 955/965). The new sensor is said to be better in sports where getting wrist HR is more difficult because blood flow to the wrist is restricted (cycling, weight exercises, rowing, ...).

I though this may be of interest:

www.youtube.com/watch

Forget about it, OHR is just useless for non static activities. That's not going to be changed.