It really depends om where you are at when you want pizza.
I prefer over all, Aurelios thin crust Chicago style pizza, sausage pepperoni and mushroom.
For Deep Dish Chicago style, Uno ( the original ) or Geno' s both have great products.
In the Quad City area ( Davenport and Bettendorf, Iowa and Rock Island and Moline, Illinois ), I prefer Harris sausage pizza or add on the pepperoni and mushrooms. There are a couple of copies in the area that are also very good. Harris is a QC type of pizza, familiar to those there.
In Columbia, MO, I prefer Shakespeare's Pizza, Canadian Bacon and Breakfast Bacon.
I the Seattle, WA area, I like Frankie's in Redmond. Sausage and Pepperoni again.
Overall, Chicago think crust is my fav and that is Aurelio's.