I've tried Five Guys twice now, and both have been very disappointing. I don't get what some people rave about.
First off, the price is insane. Over $15 for just a regular-size cheeseburger, fries, and drink! The burgers are very dry other than the weird sticky "cheez stuff" they use instead of real cheese. Even the grilled onions failed to have much flavor. The fries were nicely crisp on the outside, but have a faint taste of bad oil to them or some other off flavor I can't quite ID.
The free peanuts were quite good.