My new baby Howie!! (He was a stray and he's around 8 or so years old. I don't have the energy to explain his background lore right now) I adopted him a few days ago and he's adjusted perfectly. Pretty much the second I let him out of the carrier he was happy as a clam. (I was already friends with him though since I visited the neighborhood he hung around fairly often.) He's the sweetest, most polite boy. And also a lap boy and a couch potato. My roommates' kitties weren't overly thrilled about him, but they too seem to be adjusting fine. I think the boy cat and Howie will be friends as they're both big giant babies personality-wise.
So now I have THREE kitties following me around everywhere 24/7 as opposed to just the two. (my roommates' cats)