John,
The whole assembly is surprisingly sturdy. The hinges at the rear pillar are huge and hold the glass quiet firmly. The pistons, even after 21 years still hold the glass up without any problem. I've actually run down the road with the glass open (partially) and wasn't worried about the glass flexing. The only thing that has become "fragile" is the opening T-handle pull. I am somewhat worried the cable is starting to stretch. When the glass is shut and locked it is very secure. Still, I use it less frequently of late. The rear antenna makes it a little tricky to load/unload things from the rear compartment and you have to be VERY careful to watch anyone helping you. A belt buckle and even a zipper can easily rub the rear quarter panels and gouge the paint just by leaning over.
Later................. Nut