After a life of owning many good, not so good and two great cars, I've had the joy of replacing transmissions - okay, maybe not so joyful; what can I say. I am about to do a transmission flush at Mr. Transmission (this isn't a drain but a flush). The cars I am taking in are an 94 E36 318i and a 97 E39 528i. Both take "standard" transmission fluid; is there any benefit to switching to "synthetics" or any draw backs for that matter as well.