Just tried the 42mm Milanese loop and the 42mm sport.
Definitely prefer the Milanese loop.
Meanwhile, some of my questions were answered.
The sport is noticeably lighter.
The 38mm is definitely too small for my wrist.
The sport band is tricky to put on if you like a snug fit.
I'd be worried about the aluminum and the ion-x glass getting scratched.
The trial units are dummy units and cannot be powered on, so you cannot compare watch faces on your wrist.