Small but great atmosphere. Food is terrific. We went on a busy Saturday night (May 2015) and got right in, but you have to go early (we saw a lot of people turned away because it can get very busy).
Even with a packed crowd in a smallish space, our food was served up pretty quickly and with expert presentation. The server/bartender Robert (serving the sushi bar where we sat) was amazing. That guy handled a million things at once, and never flinched.
Overall a great downtown Madison option for any night! The bagel roll is lights out :)