So far it looks like the M3 pre-LCI iDrive is the only one that is "picky" with the LCI iDrive controller swap and the software/production date versions, as the 3-Series pre-LCI iDrive does not have such swap problems.
The only iDrive requirement in the 3-Series is having the 6 pre-programmed buttons (MY2007) and not any particular production date or TCU type. The swap works as long as it is a MY2007-on iDrive.
