A question about Apple watches offering ECG heart rhythm tracking:

My background: I'm 81, have occasional SVT and AFIB. Saw three different Cardiologists this year. The first two, seeming very aggressive, tried to sell me on surgically inserting a Loop Recorder above my heart for 24/7 HR tracking. The third, a Veteran's Administration Cardiologist, appeared just the opposite, too nonchalant. Said " Just continue doing what you've been already doing." (Just 25 mg of Metoprolol)

Heeding the advice on many on this forum, and abhoring any kind of surgery, I declined the Loop Recorder idea, but decided to track my HR 24/7 with an Apple watch. Many of you raved about how great the Series 9 is, and is being accepted by more and more doctors. Someone mentioned that the ECG tracking was discontinued by Apple due to patent infringement. Yet now, in looking for a watch that offers both ECG and fitness tracking, I'm finding the Apple Series 10 claims to offer both, and has nice upgrades as well. My question: which watch should I purchase? Is there something wrong with the ECG tracking on the Series 10 that I should be aware of? Thanks in advance.