Some, perhaps many, will disagree with me here but I think In & Out Hamburgers are fantastic. I'd go as far as to say they're the best offered by any of the "Major" fast food burger joints. I'm sure some smaller Burger places are better.
Obviously they are not as good as homemade... well, depending on how good of a chef you are.
The very best Hamburger that ever existed, (the place is no longer in existence) was Priest Valley Hamburgers.... out of Coalinga, Ca. on 198. As greasy as it gets.. and I don't care. They were to die for... which you probably would if you ate too many of them, which I DID over the years.