Personally, I use true iron sights. I've shot firearms during my adolescence and still kind of do today. So I'm use to them, and I find them to be more immersing in games.
And I hardly use VATS only early in the game when I don't have good weapons or a lot of ammo/health items. I prefer real-time, VATS makes it a bit too easy sometimes. There's no better rush than a bunch of Cazadores or Nightstalkers rushing you with extreme veracity. Or a Deathclaw running full speed, spreading out it's arms as it prepares to strike. The Deathclaws are the biggest rush of them all :gun: