The Brad Penn has been the best oil I have ever used, that being said, they have switched it to Penn Grade. I have only had one oil change with the new Penn Grade as I am still trying to use up all the BP first. I have not seen any ill effects, but then again, I do not have anywhere near a season on that brand, just one oil change.......Before that I was using VR1 which I believe is still around today, and would be my backup....The consensus around here lately is everyone is going to Driven....Haven't tried it. I am told they have both full and semi synthetic. Everyone I know is running the semi....with good results. Why the BP had to change is beyond me....My engines are so clean with that stuff its amazing.