Hey guys, I'm new to this forum and I wanted to get your opinion...alright here it goes.... I walked into a local autozone and saw castrol syntec for sale...only $3.99/qt...then I noticed they had 0w-30 in stock...I immediately looked on the serial code on the bottom...and it was an M04!! I cleaned out the whole store and another local autozone down the street...15qts of GREEN GC!! now, my car takes 4.5qts of oil...I wanted to stash up on 4 oil changes...that means I need 18qts in the end...so 3 more to go...I went to another local autozone and only found this... This is the only one I could find...including 3 other autozones I went too...now, from the research I have done, this is GOLD GC correct? How well does it perform? I went ahead and bought the 3qts of gold GC and wanna know if I wasted my money? oh btw, 18qts of GC cost me $77 out the door...not bad huh?