Shake Shack's fries are far superior, but the burgers at In 'n' Out are miles ahead.
super duper in sf is so good that I just eschew both chains. That said I tend to only get a cheeseburger at original joes and that is maximum monthly and maybe 4-8 times a year. I love cheeseburgers and have a caloric fear of eating even a 4-oz sized burger.