I have had a Rhode Island Red for 2 1/2 years. She is a good bird that is not mean, and forages well when I let her roam around. She is lead hen in my flock, but is not overly dominating to the more submissive birds. Out of my four chickens, she is probably the second best egg layer, following my Columbian Wyandotte. In her first year, she laid about 260 eggs, and hasn't slacked off very much in her second year of laying.
In terms of temperament to humans, my Rhode Island Red is not aggressive, but is not overly friendly. She prefers to wander around on her own, though she will come to you when you call her, and enjoys getting treats. One drawback is that she is quite noisy when she lays an egg, whereas my other birds are usually silent.
Overall, if you want a good layer of eggs, and a bird that is easy to find (most hatcheries sell them), choose a Rhode Island Red. But, if you want an extremely friendly, personable bird, you might want to look into another breed.