I like bettas better.
But having both in the past and at the moment. Goldfish require a big tank, around 50 gallons or more, I personally think bettas need 2.5 gallon or bigger and I know there are some members who would agree and disagree with me, so bettas don't cost as much and come in many different colors. I do like have goldfish live longer thoguh. So maybe I like both.