You don't really have to look for the Texas Hamburger Factory if you drive down Justin Road. If you keep looking to the north as you drive up and down the street (near I-35 E) you'll see a shopping center and in that shopping center you'll see GIANT letters that spell out the restaurant's name.
The place has been around for a while and does look like it. The interior is dressed up in what you would expect from an older Texas establishment. Don't get me wrong, it is clean, but the clean decorations are still old looking. To a degree it actually adds a bit of homely charm to the place.
You had better know what you want to order when you get in line. Sure the menu is hanging from the ceiling and the writing is big enough for you to read it from two miles away, but don't let that lull you into thinking that you can stand in line while you make up your mind. The lines moves fairly quickly and there is so much on the menu (mexican, bar-b-que, salads, sea food, catfish, hamburgers, and more) that even regulars are caught off guard from time to time.
As for the food, it is pretty good. Whatever you order the portions tend to be larger than what you might expect. The hamburgers are never dry, the iced tea is alsways just rights and the cobbler that is served is a must. My wife usualy orders the quesadillas. The torillas are lightly buttered, the cheese is melted and hot, and the guacamole and sour cream are cool and yummy (those are her words, not mine). Whatever you order, expect it out pretty quickly. They don't mess around with being fashionably late with your food here.
It's the perfect place to go when no one can decide what to eat. The service is nice and quick, the atmosphere is what I refer to as "comfortable", the food will satisfy, and the prices are relatively cheap. If it were dressed up a little better I'd expect a higher price tag on the visits.