Überstein operates under a marketing agreement with Hofbrauhaus (but is not owned or operated by HB) complete with liberal use of HB signage and serving only HB beers. The net effect is to make this place a mini Hofbrauhaus, which isn’t necessarily a bad thing, but it obviously limits beer selection quite severely. As of this writing, only 4 HB varieties are available: Original (a Bavarian lager), the dunkel, the maibock and the hefeweizen.
The space is fairly long and narrow, making it not especially conducive to a traditional "beer hall" setup, though during seasonal months there are a number of communal picnic tables out on the front biergarten, from which you can see Wrigley Field a block away. Staff was friendly and prompt enough, though the small crowd size was not really presenting them with a challenge. Food menu is sparse -- it fit on a card the size of a standard letter envelope -- and contains typical German items like giant soft pretzel & cheese dip, brats, schnitzel sandwich, spatzle & gravy, et cetera.
With numerous more impressive German watering holes in the nearby Lincoln Square area, I wouldn’t go out of my way to visit Überstein. However, it does present the Wrigley crowd a more interesting alternative than most of the barf-holes around the stadium.