Hi, I bought an additional screen protector for my new Edge 840, which is made of tempered glass. It does not have any bad influence on the touch screen so far.
However, what do you think about tempered glass as a screen protector in contrast to a simple protective and flexible lamination sheet or film? In former times, I used such a sheet without any complains for my 830. But now I switched over to tempered glass, which might be more risky when it comes to crashes, downfalls or the like.