My wife and I used to frequent this place when we moved up to Chicago, as it was the Spanish restaruant that I'd gone to when in high school. That said, the quality of the food and overall experience has been sliding ever so slightly, as well as the portion size of the tapas, without a slide in prices.
You will still get a decent fill and good degustation from dining here, but the quality problem is soon to become an issue for this restaurant in the near future.
Recommended Dishes:
Fried green peppers with salt
Gazpacho
Garlic Shrimp
Plato de la Casa
Pincho de solomillo
The desserts here are awesome and won't kill your stomach!
Not-so-recommended dishes (but otherwise clearly edible):
Ham and chicken croquettes (the mix can be too salty at times)