Don't think the OEM Bluetooth integrates particularly well with the MFD2, as it's more designed for 3rd Gen head units (RCD & RNS 510), to get the onscreen phonebook etc.
I had a Parrot CK3000 evolution unit fitted with my MFD2 using a quick-connects CAN harness, and it worked fantastically well. Excellent sound quality, full integration with the MFSW ( be it the early 2 phone button one or the later one button one). Voice dialling on my 3GS (using IOS 4) worked surprisingly well too.
As for coding, well there isn't any, it was truly plug & play. Unless you want to upgrade to one of the later touchscreen head units, in my option it's one of the better and most cost effective options.