What plastic are we talkin about here? I cannot speak for all the other folders ,, just back to the original post about a Dahon .... Thats a pretty hefty chunk of steel in there. The only "plastic"is a piece of delrin which slides the quick release, instead of being metal to metal which would increase wear.
The new latch is a pretty neat piece of engineering allowing the stem to only unfold if the quick release is ALL the way open. Even without proper tension ( which is even adjustable ) the stem will hold 100 %.
All I can think off being plastic is the outside "hook" which is the second preventer of a loose quick release. That one might break if you run it into a wall, like many other items which will break, if the speed is big enough..... ( not Dahon specific and not even folder specific , if you crash hard than forks wheels headsets and what else not needs to be replaced . But even than I would bet that the latch will be still workin.
Thor
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