Ive never eaten In-n-Out, though have heard good things.
since its relevant Id thought Id take the opportunity to post this up-
http://www.hamburgeramerica.com/ha_george.html
The guy who made this is one of my best friends brothers... hes a freelance photographer, he made a documentary called "Hamburger America" and also wrote a book on burgers joints across the US. he has tried and wrote about some of the strangest and best burgers in America
. hes a real good guy and makes a damn good burger. check out his website