Ian and I stopped here for lunch Friday afternoon. We got there around 1300 and left around 1400.
I ordered a #5, cheeseburger with hickory sauce and mayo, double meat. While I liked the burger a lot, next time I am going to get it with just hickory sauce. The hickory/mayo mix was close to Utah-style fry sauce. The burger had a nice crust to it, and was done medium well, with a wonderful flavor to it. Ian got a cheeseburger with catsup only.
I also got a small chili. It came with a bunch of tortilla chips. The chili had a great medium-thick consistency, had decent flavor, but little spice heat. It comes by default with cheese, onions, and jalapenos, all of which I asked to be left off so I could check out the chili.
Service was good. The tea was good. Our check was about $22, which now that I think about it was a bit high. The burgers were $6+, as was the small cup of chili. Everything was ala carte, so even the fries Ian got were $2.
So overall, the burgers were pretty good, but Flat Tire seems to be a bit more expensive than I would want to hit regularly. If I brought the family there, my cheeseburger dinner would be almost $50.