Imogen almost always comes when I call her. She is so very attuned to my every move, it's scary. Even if she's asleep, when I leave the room, she will wake up and follow me. In fact, just a few days ago she was happily cuddling with DB for a nap while I showered, and DB reported that the moment she heard me open the shower curtain, she shot out of his arms like a bullet to come jump up on the tub and greet me, even though I'd only been gone from her sight for less than 15 minutes!
The only time I've noticed that calling her has little to no effect is in the roughly two-hour window from 9:30 to 11:30 at night, when "night crazies" are either building up or winding down. I suspect that's her daily moment of "I am a wild, undomesticated creature, and I shall not debase myself to come when called." Hehe.
Everyone who's met her says she's more puppy than cat in the way she loves people and wants to be around us. Not gonna complain, myself.
