Oh and also, Portillos is nothing special. I live within 20 minutes of three and I go maybe a few times a year. Its good food but I feel like its good food for midwest people who dont leave the midwest.
In recent years, been out to the NYC area (used to live there awhile), Boston, Maine, Washington D.C., Atlanta, Dallas, L.A., San Fran, San Diego, New Orleans, Baton Rouge, Tulsa, and probably a few other I'm forgetting, and in some cases, several times, as well as many cities within the midwest (Milwaukee, Green Bay, Detroit, Minneapolis, Indianapolis, Des Moines, St. Louis, Memphis, and also probably a few other places I'm forgetting), and I would put Portillo's up against any burger joints in any of those towns at any time.
I have a very limited palette and am a extremely picky eater. I'm basically a meatarian. My diet basically consists of burgers, steak, pizza, and basic things. So I eat a ton of cheeseburgers to say the least.
Smashburger is good, 5 guys is good (big thing on the quantity here...), whattaburger is good, Shake shack is good, Fatburger is good, I have enjoyed in-n-out on the west coast, etc, etc... All have something good about them.
Portillo's is also expanding into Arizona and Florida as of recent and most people there seem very receptive of it. So it must be equal to, or better than other local options.