By itself, I prefer Pepsi because it contains a little less carbonation - It's still a little too sweet, though, so I like it cold or not at all.
Though in mixed drinks Coke is superior, IMO. In that context, Pepsi goes too flat and is still too sweet.
WRT the Crown and Coke reference above, I prefer Ginger Ale instead. Stays Crisp.
Except in the summertime, then it's Stolichnaya and Cranberry juice.