Made the switch from S21 to 15PM. Pros of the iOS is the ecosystem if you have other Apple products. It’s just so seamless ie with the MacBook and iPad. I do like the Face ID, easy to access the phone.
I do miss some of the functionalities from the Android. Such as the keyboard responsiveness, left or right swipe to return back to the previous page, notifications status and reading notifications.
I’m in the same boat. Thinking either S9 or the new SE. I will just be using the normal features of the watch.