I am no connoisseur, but I like Ben & Jerry's Karamel Sutra (an absurd amount of sugar) and Häagen-Dazs Rocky Road (a slightly less absurd amount of sugar).
Does anybody remember Stop and Shop Vanilla Bean Ice Cream? Man, that stuff was actually exceptionally good (as I recall many decades later!). Today, I have to say Haagen Dazs Vanilla is really good.
Then again, I have no doubt there are plenty of super-gourmet ice creams out there...but I actually don't go out and eat a bowl of ice cream more than maybe once or twice every couple of years...so I am definitely no aficionado.