Having grown up in the midwest, I'd played up Steak 'n Shake to AZ friends for years... Well, I had to eat some crow after my burger, LOL.
If you're expecting the Steak 'n Shake of old (both food and experience-wise), you're going to be disappointed. Great location. Great people watching from the patio (which was dirty). This location is a stripped down menu version. Burgers, shakes, fries, hot dogs... No Chili-Mac, etc, etc... The well toasted buns and thin edge burgers have turned into a bit of an average, slightly mushy, OK tasting burger. The fries are still great. Had this been a blind taste test, I'd have never guess Steak 'n Shake (and I spent 20 years of my life eating there).
In short, decent food for a decent price on Mill... If you want food that tastes like Steak 'n Shake used to, go eat at a "Freddy's".