The MMX 300 headset is often compared to the cheaper DT 770 PRO , most times with the reccomendation to use the DT 770 PRO together with a low-cost stand-alone microphone.
The fact, that the MMX 300 not only has a headphone in studio quality, but with the integrated gooseneck microphone also has a microphone in a similar form is used for professional recordings in the recording studio, is ignored in most cases.
Looking at the unit price for comparable headphones and a corresponding microphone, it is clear that the price of the MMX 300 is quite appropriate.
Cost savings at this point almost always mean quality loss in voice transmission.