I have lost just a few teeth, and I believe I have a mass produced saw. That said, I would bet that most of the wear and tear I have put the ryoba through could have been dealt with more tactfully. I was using it to cut saplings and smallish trees, and sometimes the saw was getting torqued inside the kerf, etc...so losing only a few teeth over this long is a win as far as I am concerned. And with sections of it that have no damage done at all the saw still works just fine. All the lost teeth were from the fine, higher TPI side where the teeth are both smaller and offset, for what it is worth. I have not knocked out a single one of the beefier teeth yet.
SOM