The OEM trim rings had multiple spring attachment clips, and once they were snugged down they won't move. The more recent after market rings have four clips that really bite into the wheel. Mine have never moved. Once they are clipped on they are very tight.
I have yet to hear of anyone having a trim ring snap a valve stem from rotation.
I have owned 3 69 Z/28s: Garnet Red 30,000 mi unrestored.
Glacier Blue, documented Canadian Z
Rallye Green purchased new in 1969
1968 Camaro Coupe L30 275 horse. ]