the internet is full of miss information, but the glock problems are (were) real. At the beginning the gen 4 had problems with the recoil springs, the new ones were modified a couple times until they figured one that worked, that one is 0-4-2.
After that, people started complaining of BTF (brass to the face) and erratic ejection patterns (ejector 336), so glock replaced their ejectors with another one that I cannot remember the number but I think is 2286. I have seen many glocks, and they all have erratic ejections, some more than others, some, have a weak ejection, some eject to the left every once in a while and so on. So there are little problems with the glock that can be fixed by replacing a couple parts.