I use Titanium shaving razors and the look of brushed and mirror polished Titanium is liquid and lustrous.
The screensaver and website animations on 15 Pro seem to represent some sort of powdered coating (a guess) and perhaps that is representative of PVD....the coating is used in high end watches to protect against scratches anyway.
So use of a case may be moot for IP15 Pro.
"One of the remarkable advantages of PVD coating in luxury watches is its exceptional scratch resistance. The hard layers created through this process act as a barrier, safeguarding the underlying metal from everyday wear and tear."
Apparently, PVD coatings can also wear off, depending on the expertise of the facility that does it...which means
natural Ti seems to be the most prudent choice (for me).
I dont know whether PVD affects the lustre and sheen of uncoated Ti...we shall see...but for now, I will use without
case. Screen protector, a big YES!