Mercedes Keyless vs. Regular Key

Comparison: mercedes fbs3 keylessgo vs. non-keyless keys

FBS3 keyless key:
315mhz/433mhz- changeable
used when all keys are lost
works for C-class W204, W207, E-class W212, R-class W251, S-class W221, W216, CL-W216, CLC-W204, CLE-W207, CLK-W207, GL-X164, X166, GLC-X204, GLE-W164, W166, GLK-X204, ML-W164, W166

MB KeylessGo key supports USB cable write data and infrared write data
Infrared write key must be loaded with 51 types of data files, and installed batteries! After matching with this key, it has the same keyless entry function as the original car key.
When you open the door, you don’t need to press the remote control. You can press the button of the door handle to unlock.
There is no need to press the key when closing the door. Press the button of the door handle to close the lock.
After matching with this key, it has the same inductive one-key start function as the original car key.
No need to buckle the one-key start button, no need to insert the key into the lock, one-key start and one-touch start.

Mercedes regular key (non-keyless):
315mhz/433mhz- changeable
used when you have a spare key;
can be used on almost Mercedes with BE keys

Conclusion:
Both keys can be rewritable and reusable.
Both keys can be programmed with Xhorse VVDI mb tool, vvdi, autel, etc.