I run it in my 2014 Mustang GT and went 7,200 miles on the last oil change and the oil looked almost new on the dipstick. The inside of the engine that I can see looking into the oil fill hole looks clean as it can be.
The car just turned over 19,000 miles and I've not done any Oil analysis on any of the changes but I don't have a problem using it and think it's a good oil.
I have a friend who own's a 1998 Chevrolet K1500 truck that he bought with 76,000 miles on it. The truck now has 383,000 miles on it and for most of the time he has owned it, he ran Trop-Artic which is also made by Conoco Phillips. He said he has run Quaker State for the past few years but the majority of his miles that he has put on were with the Trop Artic. His truck still runs good and the engine is quiet.
Wayne