My sun conures are louder than my blue crowns. The blue crowns might scream a few times a day, but the sun conures do it constantly. The sun conures are more prone to biting. My blue crowns will nip at me if I try to get them to do something they don't want to. My blue crown is a right-handed bird. He will not step up onto my left hand. If I push it, he will eventually bite me. The sun conure bites just because he can. The difference for my birds is that the sun conures tend to give a hard pinch, but with that needle-sharp beak, my blue crowns will actually hurt you.