I visited 575 Pizzeria four times in my two week stay in Amarillo. At one dinner, I shared their Caprese which was among the best I've had in any of my travels.
My pizza of choice, and the one I got on each visit, was the "Double D's Triple Pep". I got it as a small, personal pizza the first time and, on each of the other visits, I got a large so I could take it back to my hotel to have it for lunch and the next night's dinner.
It's not the cheapest pizza, but its quality ranks near the top of my list in Texas.