As one who lives in Oklahoma City and has worked in the metro as a police officer for nearly 30 Yeats, I liked the show for some of the local references and nostalgia.
I hated Grace's character but enjoyed the show for entertainment purposes. Sometimes the local references and "Okie" sub culture and nuances were way over done, but I suppose a TV show is bound to some of this in its attempt to present the flavor of the locale. The police "technical adviser" was either absent, incompetent, or regularly ignored by the director, but that's common for TV shows, and ruins everything for those in law enforcement.
I'm wondering if Johnnies restaurant's owners are related to the director or screen writer, as their food is either portrayed in every episode as if it is the only restaurant in the city.
I really have noted no scenes which include the actors shot on location, other than generic shots of a few landmarks which occasionally appear; other than that, I have to assume most everything else was shot elsewhere.
I found it a bit corny that every one of the main characters' last name is that of a city in Oklahoma.