I really hope my unease around kids changes for me with my own. Everyone tells me it will be different. I just hope they're right XD
Coming in a bit late to this party, but as a dad with three girls (9-12 range), I'd have to say, yes, it's a hell of a lot different when they are yours. Sure, they'll sass you, challenge you at every turn, and essentially try to hack their way through a good part of their responsibilities. But after the chaos settles and you all have a chance to sit down together as a family, it's worth the anguish.
Of course I'm still waiting for that day when they finally say: "You were right, dad."