I realize I'm in danger of being stoned for saying this, but I really am not that big of a fan of the burgers at In-n-Out, Steak'n'Shake, or Culver's, even though I always hear mad raves about those places. I like some of their other food, but for some reason, just don't particularly care for their burgers.
I'm actually searching for the first burger love of my life. When I was growing up in the north, there was a chain called Bill Knapp's that had (to me, a least) The Best Cheeseburger Ever along with The Best Chocolate Cake. I've never found anything that came close, although TooJay's Deli does have TWO varieties of chocolate cake that were pretty killer.
All I can say is, I'll know true burger love when I taste it!