Yes, I got worried when I first heard about premature deterioration in lenticulars. The half dozen I have are all fine (oldest is 24 years old) so I suspect it is a heat/humidity issue.
Mark
it would be my suspicion that different methods were used to manufacture them also. As they moved along, they probably found some adhesives worked better than others, lasted longer, weren't caustic or have chemical reactions over time that deteriorated the plastics
I have a 40x60 for Zathura. It's been in the warehouse for 10 years (hot in summer, cold in winter) and I see no deterioration, though I sure would like to see someone say "how much" and "Great, I'll come pick it up!"