In Chicago, it all depends where you are. You can eat fantastic Mexican food if you're willing to make the trip to Pilsen, Hermosa, West Town, or one of the other Mexican enclaves. But the overall standard in most of the North Side, particularly near the Lake, is astonishingly poor. It's not like LA, where I hear you can walk into any Mexican restaurant and be assured of a good meal. People there all know what the food is supposed to taste like and the mediocre ones just don't survive.