In N Out all the way. And I've lived on both coasts.
In and out hands down. Double cheeseburger animal style rocks.
5 Guys for sure. They hyper here in Utah is ridiculous. It's only popular because it's from Cali...OOhhhhh ahhhhh! Phhhtt.
<b><u> FIVE GUYS
Have 5 guys up here and I'm not impressed. Haven't been to an In n out since I was a kid, so I don't remember those. Frankly, I think Jack in the Box has better burgers and they are far cheaper (as far as chain stores go).
I have only had either of them once...so I don't think I am really qualified to answer!! :)