Well, I can say from experience that unless you have AFIB, or other heart problems, the ECG "feature" once you've played with it for a few times, is nothing more than a "Hey! Y'All come see what my watch can do" type thing. I have an Apple Watch, along with the Active 2, and am currently trying to decide which setup (iPhone 11 Pro/Apple Watch vs. Samsung S20 Plus/Active 2) I want to keep. I am actually more interested in the fall detection, and notification of emergency services (My Active 2 is LTE) than the ECG, as I don't have any known heart problems.
I've been trying to get info on when/if the fall detection will ever be introduced, as well as the question of will I be able to contact emergency services if the need arises, even though I don't have the watch assigned to a carrier. I know the Apple watch will do that, and not only contact emergency services (and my emergency contacts) with my "SOS", and location in coords, but for the emergency services it will also provide my medical info, allergies, blood type, etc.
That's a big thing for someone over 70 like myself.
Good luck with your update, I'm about done trying to get any type of information out of Samsung, they're tighter than "Tillie's tush" and quite frankly, I'm tired of waiting. The Series 6 Apple watch purports to have not only the features Samsung promises but can't deliver, but Blood Oxygen content, and there's even rumors of Blood Sugar being able to be measured from the blood flow.
To me, that's innovation.