[Batje]

My experience for BMW on the latest firmware:
CAS1-OBD good
CAS2-OBD mostly good, had EWS tampering fault code with no-start once.. cleared with ISTA/D sync.
CAS3-OBD good
CAS3+(+)/encrypted /ista-p version-OBD very bad! downgrading bricked a few CAS modules -> much safer by soldering and making key from EEP dump.
CAS3+(+)/encrypted/ista-p version is very good if you do it via File make key. DO NOT write new EEP dump back, even if it tells you to. The key will work fine without writing back the modified dump and in fact writing the modified eeprom could brick your CAS in my experience.
CAS4(+) via soldering also very good and safe. you need good skills with hot air soldering and good flux.
FEM/BDC- only tried once on a bench setup.. worked fine with the test bench but never tried it on a real car.

What are most experiences with the FEM/BDC?
Problems with programming? Bricked FEM/BDC?
Keys not working? Original keys not working,....?