I haven't broken a hinge yet, but I did have one work itself out and get lost. I replaced it with one from a rarely used systainer and ordered a couple of spares.
Only damage I've done on a systainer is when I stood on it, I split the lid slightly.
Annoyingly it was a FOG.tainer
Pretty sure the plastic must be thinner or something cus I have stood on all my other systainers and T-locs no problem unless I just stood on it funny.