The fries taste like they ground up some pringles and shaped them like fries, dry and flavorless, and when I say flavorless I mean I can't even detect potato in there, they might as well be crispy air, no idea how they do that. The hamburger patties are so thin it's actually hilarious, similarly dry as fuck, and if they weren't salted to hell and back they wouldn't have any flavor at all. I gave them a few shots at multiple locations because I have a few friends that rave about them, but I still haven't finished a meal there.
TL;DR In-n-out tastes like dehydrated McDonald's, and I don't even like McDonald's