These are nice chickens, but they appear to take a long time to mature. I have the buff variety, and my oldest Orpington should be about six or seven months old now. She appears to be about the correct size, but none of my roosters are interested in her, and I haven't seen a single egg.
Orpingtons are said to like to be held. In my experience, they don't care for it at all unless handled when fairly young and it is continued frequently.
Of the Orpingtons I've experienced over the years, they haven't been terribly hardy. If they're not the first to get sick, they often seem to get it worst when it comes around. They also tend to cower before the other chickens if they are not one of the first established. I even had some of my mixed-breed flock kill one of mine a few days after it was introduced -- it appeared to have been cornered and then relentlessly picked on. They don't seem to stand up for themselves all that well. The one rooster that was tried was almost instantly dominated by a sex-link mix and was even picked on by the hens.
Still, my oldest Orpington hen is a nice chicken, fairly high-ranking, gentle though firm when it comes to establishing the pecking order; and while she did pass a round of sneezing about to the rest of my flock, she appears to have stood up to it pretty well.
My youngest Orpington is undersized. She had a badly injured leg, so I got her for free at the same time I was buying other chickens of the same age. She recovered fully, apparently quickly, and is as sweet as the breed is reputed to be.