Flex Joint or no?
Yep, same system I have.
Do you have any resonance vibration? I just drove mine home from the detailer (my clearcoat had some oxidation and scratches), and I noted that I don't have it at all around 65-75 mph, it's more around 55-60 mph. It's not bad enough to worry about, I was just wondering what people do.
My detailer did a great job, see pic.