We have all been to Mr. Beef (in my case, many times), and I can say, with no doubt, that Johnnie's, on North Avenue in Elmwood Park, rules as the tastiest, best made, and highest value Italian beef sandwich in the western suburbs of Chicago. The beef is tender and flavorful, and the French bread roll has consistency of shaving cream -- paradise. My suggestion: go with the "hot and sweet" peppers.
The fries are perfect (they have such high traffic, the fries are always "just made.")And you get a few more than you can reasonably consume.
Italian lemonade is an ideal complement to beef and fries.
I have actually bought the beef, brought it home, and enjoyed with a good bottle of Chianti. Try it.
One caveat: you MUST have your order ready when you step to the counter -- or you will be stepped over.