As you can see in the chart below ... For the general fitness comparison, the COROS VERTIX 2S performed best for GPS accuracy, the Garmin Forerunner 965 best (or least iffy) for heart rate ...
The Garmin Fenix 8 and Garmin Forerunner 965 are both among the best ... which helped me to pace my race. To compare the accuracy of the watches on the day, I kept an eye on the distance recorded ...