I've kept mine on, ordered a cheap tempered glass which went on perfect minus that ugly circle for the fingerprint sensor. The fingerprint sensor barely worked, I'm thinking probably because I had left the stock screen protector on underneath it. The stock protector feels good and barely noticeable but I'm considering taking it off and getting Whitestone dome or amfilm ultra. My concern is that they won't fit with my Defender case. I've barely used screen protectors since the s6 edge because tempered glass never worked right for me on the curved screens and I wasn't good at putting film on without bubbles.
Amfilm made a good tempered glass for the note 9 but they broke easily, didn't fit with Otterbox defender etc... I have actually never broke a screen (knock on wood) in my 24 yrs of using a cell phone and the majority of that time was with no screen protector. I have however, scratched many film protectors and shattered many tempered glass protectors. Funny enough when I have dropped my phones without a protector on it, there has never been any damage. Defender cases and even medium size cases have tended to keep my screen from touching any surface I've dropped a phone on. One of my phones even survived unscathed a fall on rocks which I'm sure the screen did come into contact with the rocks. I think the tempered glass breaking many times wouldn't have broken the actual screen based off of most of my experiences. It's more of a mental insurance for me I guess.