Whitch synthetic oils are the best quality?

retail store brands vrs manufacture brandsWhitch synthetic oils are the best quality?
Any synthetic is good.Whitch synthetic oils are the best quality?
I have heard lots of claims that Amsoil is the best but I always use Valvoline SynPower, not because I think it's the best but because I think it is good and because the parts stores I use do not sell Amsoil.
Oil is controlled by the American Petroleum Institute (API) and all oil must meet their specs. for quality. So one is no better than the other no matter what the ad says.
They are all made in one of three plants, all are good.





The more expensive brands are the ones that spend more money on advertising and racing sponsorships.
Lots of opinions on syn. oil...but you can't go wrong with Amsoil.
People have their favorites but they are all good.
tronary is stupid.
ROYAL PURPLE dooooo ittt