Really all of them are good oils. Pennzoil YB has been getting alot of rave lately. Really just choose Pennzoil YB, Quaker State, Mobil 5k, GTX, or Valvoline and feel comfortable it is going to do good job under regular service. Personally I dont know enough about the different brand to recommend one over the other. They all get used a lot and produce very good UOA's. Pick one that you like and just use it. If you really want to try to find which one you like, go to the manufactures sites and look at the different data sheets. In Ohio, just pick the one that has the best cold weather properties and go with it. I think you will find that between them, there is little difference.