Dear DavidM,
I found this thread too late to suggest anything, or I would have said that for the best steak in town your hotel was just as close to Keefer's, which on this forum has often gotten the highest praise among Chicago's many excellent steakhouses, as you were to Smith and Wollensky (also great though).
But I am glad to see that from the choices on your short list you picked Frontera Grill. That's what I would have picked if I were you, or if I had the pleasure to take an out-of-town visitor to dinner here.
I am just sorry to see you've already come and gone because I am dying to visit England again and wanted to ask if you wanted someone to carry your bags for you on the trip back ... oh well, better luck next time!
"Your swimming suit matches your eyes, you hold your nose before diving, loving you has made me bananas!"