They're all kind of the same except for some Mom and Pop places. I've traveled Iowa for 40 years and the best convenience store breakfast is at the Co-op in Hull, Iowa. I go way out of my way just to have breakfast there. Only place with a real fried egg sandwich. Made fresh, choice of fresh cooked sausage patties, fresh cooked bacon or fresh cooked ham. On buttered toast with cheese. Very reasonable price too. Go early because when they're out that's it. They don't hold tons of stuff in coolers. They also have the breakfast pizza but that sandwich is just right with the egg done over-medium. If you ask for it any other way they'll be more than happy to make it for you. They also have great hot lunch choices in their take-out case. A typical day will see a choice between one of two plates. Like ham, real mashed potatoes and green beans or meatloaf, real mashed potatoes and corn. All home-cooked. Tell your doctor to back-off. Small place. Good parking. At lunch-time those plates are moving out of that hot case as fast as they can put them in.
The QT chain in Iowa is very good for a few things and the bigger ones have made to order carry-out. They have a really good breakfast sandwich that is a fresh made grilled cheese, with a fried egg (reheated but not terrible), choice of bacon/sausage/Canadian bacon (reheated but good quality) and a tomato slice with lettuce. Again you can roll your own because the ordering is done by customer input on a screen.