I've using the watch for a month now. In that time it did crash while outdoor workouts. While recording it suddenly showed the current time and although already recording for something between 30 minutes and an hour, there wasn't a trace of that workout. Simply gone.
It happened with three different firmware versions and the last time with current one (22.214.171.124). After an hour of walking. The other crashes were while outdoor running, after something like 5 km. I was wearing a short sleeved shirt, so not anything was in contact with the watch. Battery always been far more than 50% loaded.