I wouldn't trust the tech at the Genius Bar too much. Someone recently wrote that the tech couldn't (didn't know how) change the exposure time of a photo from 3s to longer in the camera. I don't deny that resets can be caused by hardware errors, but from what some people have written, after exchanging phones for new ones they still reset. It seems that the problem is quite common, so maybe Apple will look into it. I'll wait for the 18.1 update and see how the phone behaves then.
i agree 100% with you. Going through an exchange is not a good thing too me: my unit is ok, my screen is very good and the chances to have a bad / uneven screen are pretty high.
Not to mention the fact that the replacement phone would come in a white box, and whether it’s new or refurbished, we can’t know for sure. But the thought of having to replace my 20-day-old phone with a potentially refurbished one really pisses me off!