SA620 is coding AND wiring for voice recognition. Ordering SA620 gives you a 26 pin blue connector for VR.
On the other hand the solution is straight forward. You need new and uncoded ULFs to get VR to work in a car that is not equipped with SA620 AND you need the dealer to not mess with the car unless they want to spend the time to enable the coding for SA620 again.
If you purchase a ULF from Europe second hand, it is most likely NOT going to have VR. If you purchase a ULF module new/uncoded from the US, you whoudl be typically fine as long as you do not have dealer code the car.
I only get the new/uncoded versions as they are configured for BT and VR. It is the best and easiest solution to make sure it works as designed
Martin
www.bimmernav.com