Why I hate Cheek Filter Gas Masks

Lots of reasons why I hate cheek filter gas masks such as the M17 and the Warsaw PACT clone masks based on it.
When the M17 went into service it did everything wrong, you couldn't change the filters in a CBRN environment, the mask weighed more than the previous M9 respirator and it was also bulkier.
These masks are interesting collectors pieces but would have been horrible to actually have to rely on in a CBRN situation.