I actually really like this apparaoch to bluetooth. I kinda prefer it over a more integrated unit.
cons are its looks bad and you can loose it
pros are: you can improve the unit over new iterations much easier, if the baterry dies on the unit just get a new one. and you dont have to worry about the headphone sounding worse plugged in.
Ive seen this before in the m50x Ive always wanted this on more headphones 
These look pretty cool. anyone heard them?
they are a really nice looking headphone. I heard they had issues upon demo so they went back to the drawing board regarding them, hence they’re delayed. haven’t seen anything about them since I saw them surface a month or two ago.
Not including the bluetooth module, these look like the Klipsch HP-3 and Fostex TH500rp got together and had an illegitimate child and Hifiman decided to adopt it, lol.
Double post sorry 