I recently ran a 10k race with my friend. I used my Watch 6 classic and I had my Flip 5 with me. My friend ran with his Apple Ultra v1 watch. We compared distances recorded for the 6.2 mile race. His showed 6.39 miles, for an error of 2.7%. My Samsung health app recorded 6.63 miles, for an error of 7%. When racing, this is important because a false longer distance means a false faster average pace. His watch has a dual band GPS sensor, while my 6 has a single band sensor. But the Flip 5 has a dual band sensor, which was connected to my phone over BT. After chatting with Samsung support, I was told that if you use the health app on the watch, you will use the watch's GPS function, regardless if it is connected to the phone or not. If I wanted to use the phone GPS, I should use the running function on the health app on the phone. If I do that, however, I'll only see my heart rate on my watch, and not see things like distance or pace. Also, my Vo2 max isn't calculated for the run. This is a clear disadvantage for serious runners to use Samsung over Apple. It seems to me this would be an easy fix to allow the phone GPS to measure distance whenever the watch is connected to it, and to use the watch GPS when it is stand alone.
