Quoted from vicjw66:
New Coke did win taste tests over Coke Classic but the tests were flawed just as the "Pepsi Challenge" tests were flawed. The taste tests involved tiny cups of each (maybe 2 or 3 ounces). The sweeter New Coke and Pepsi tested better in these small doses however people drink 12ounces or more at a time. And with that much soda Pepsi and New Coke are too sweet and tested poorly over the smooth toned down taste of Classic Coke. As a cola affectionado I agree with this. Same reason sodas with corn syrup are not as good or smooth tasting as those with sugar plus they have a funky aftertaste. Funny thing is that when Classic Coke came back it came back with corn syrup and not sugar. I will only drink Mexican coke.
The Mexican Coke with real sugar is noticeably better. I always grab a bottle whenever I find it.