didnt chance it. went with the latter one even though the serial is slightly different. I rang Audi and they said that based on the model of the car, the serial of the replacement is actually the unit that should be in it. Maybe the drivers side was replaced already. In any case, I decided to go for it because I mightn't get it again. €800. The chap in Audi said they are €4,874 new 🫠