Ouch. I didn't know they had trouble that early. I believe the E46s used GM auto transmissions.
BTW, I think I may have found a durable FCAB: the Powerflex ones have a design that reduces the forces that tear up the OEM ones. I have the UUC versions, but they look to me like rebranded (and recolored and more expensive) Powerflexes. The ride isn't any harsher, and you do get a bit more steering feedback, as it feels surprisingly closer to the Cayman.