Hi GlassOnion,
I have read several places that the Mealies are calmer, overall, but I have a DYH, and he's not lived up to the legend. I think that, overall, they are largely one-person birds but many animals have their favorite person but are quite social. Mine came around to being really social, and has even developed some man-crushes even though 2 years ago he hated men b/c of his previous owner. He's not particularly noisy - we do have "scream-fests" and it's a shared experience and includes other sounds mixed in with the screaming. I figure he's a bird - would be like telling a dog not to bark. It's only once every 1-2 weeks.
From the sources I've used for my edification, it seems that the breeders can play a major role in the shaping of their personalities - a good breeder can make all the difference between a well-socialized and more physically affectionate bird, and one who is less tolerant and more aggressive. I think what can be accepted as true is that they are very loyal and are very goofy.
Keep reading, and maybe meet some birds in person. You'll know when you meet the right one, and I'm looking forward to a lifetime with mine!