All major brands of oil and very good, and who makes the best is nothing more than an opinion and speculation. IMO, there is no best, as they are all good. A company producing inferior oil will not stay in business very long. Buy any major brand and know you are buying the best. I personally use Pennzoil for what that is worth.
Penzoil makes Quacker State Motor oil
mobil makes the oil
Advance motor oil is made by Coastal
PEAK makes peak motor oil, they are known for their antifreeze products before they launched their motor oil line. It's apparently already sponsored the IndyCar when it was first launched in 2007, and is being called "premium motor oil".
Omni specialty packaging makes the orilly brand oil
Omni specialty packaging makes the orilly brand oil
Advance motor oil is made by Coastal
The best motor oil for you car depends on the car. Many old cars can only handle regular motor oil.
If it is the conventional oil it REALLY does NOT matter who makes it. Most conventional motor oils are the same. With conventional motor oil just use the recomended viscosity and change it often.
Mobile is the the best motor oil
Edmuns.com has an article on it which says that ExxonMobil is a blender of Honda motor oil.
If you go to the Mazda web site it states Castrol motor oil is used.