I don't know personally, but my GCs breeder, who also breeds crimson bellies, told me that crimson bellies tend to be more aggressive and nippy than GCCs. Don't know how true that is?
My crimsonbellied is a bully. He only likes my Australian King who won't have a thing to do with him. He will go after every other bird including the bigger Alexandrines. He has no fear. Gotta love him tho!
My GCC can be pretty nippy when hes in a bad mood (I have a few bite marks from him on my hand at the moment, actually.) but that's the only time he really ever bites, other than when he doesn't want me to move him or when he wants to go somewhere and I'm not taking him there.