I reckon there was only 1 benefit of FRM3 over FRM2 and it was not worth of upgrading it.
If I remember correctly, it was follow me to home lights on, after locking the key on FRM3.
About later part of your questions, yes coding procedure is same.
RETROFITS: LCI Conversion - LCI Xenons - LCI Tail lights - Memory heated seats -
Folding mirrors with auto-dip - Rear PDC - CIC with DAB Plus - Combox - 6FL - 6NF
- 6NR - BMW live & Internet
MODS: Eibach Sportsline - AluFelgens CS7 - JBL MS-8 - Gladen components - SWS-8