I wouldn't bother with Royal purple at a premium price.

My opinion is that it is all marketing hype. There are no Royal Purple refineries. They buy bulk synthetic oil, perhaps they add additives to it, put it in a nifty purple bottle and sell it for 12 bucks a quart.

 

here is my take on royal purple i had my transmission service when i got the car and the tech that did it used to wrong fluid so it didn't like to shift into first or second easily and i have used royal purple oil for a while now and i noticed that they have transmission fluid for a4's so i shot them an email and told them the issues that i was having and the guy David shot me an emailing me back letting me know what kind and how much to use and he stated that they don't see to many audis using there products but he wanted me to call he so i did told him my transmission issues with the car and he told he he was going to contact the closest place that sells there transmission fluid and have them pull it and he would "right it off" and if i did not see a differance in 30 days to call him back and he would refund me anything that i payed to have it installed and he would pay for me to take it to the dealership to have oem put in.

Well it's been 3 months and it is as smooth as butter