As i stated before. Castrol is better then mobil 1 and redline it only falls to amzoil but it was so close it was almost a tie. Castrol from what i understand has the most r&d. They pioneered the synthetic oil and it is still a synthetic oil. They have just added some parts from the petroleum oil to it because there research has told them it will perform better that way. I have used Castrol in my camaro at the drag strip and the one time i changed to amzoil after the race i pulled the dip stick and had a burning smell. I am going to stick with castrol. I dont care what they put in it. Its cheaper then amzoil, It performs almost as good (I think its harder to breakdown), And it is better then all the other oils out there.