I love Portillos!
I try to go everytime I'm around one. And the one in Tempe maintains the same quality as those shops in Chicago that they emulate. I'm a big fan of the Italian beef sandwiches, especially, but also the Chicago dogs, sausage sandwiches, and even their salads.
If you grew up in Chicago, you will not be disappointed. If you didn't, you'll soon want to visit the Windy City.