I've never in my life yet played with aging on, but for the longest time I would spend ages making a Sim and building a house, start playing for like, 3 Sim days and get bored anyway. I don't know why, but I have COMPLETELY gone the other way now. I still take some time over a Sim and house, but I am much more of a 'player' now, so I am almost certainly going to start playing with aging at normal. I don't know if I'll be able to bear it when animals die though. It's too sad when even animals that are just pixels die!! :D