Every time I feed Kush, a couple of crickets will go hide in the crevice at the bottom of the cage, but they don't really stay there. They eventually come out and crawl up the screen and become lunch! I was worried about that at first, too, but it hasn't been a problem.
That is a matter of your chams toe and foot size lll cages are fairly strong so yes a toe nail could come off before the mesh would give but I have 13 chams and this has not happened. Funny thing is I give them lots of foliage and branches yet they love scaling the screen go figure !@#$. As long as they have lots to climb on should not be a worry.