I've had heard from my father's generation that this place is best for Khinkali. I went and tried it. They really have good Khinkali, but not only here you can find it. Plus the place is underground and not really the home of aesthetics, thus I'd suggest to visit it only once, if you end up near Freedom Square and are hungry.
The atmosphere is not as great, as the place is underground and daylight doesn't reach much down there. But they serve very good Khinkali and quite fast. If you're a local-taste-seeker, you should definitely visit the place.
Su-Sa: 10:00-22:30