Vl D.
Yelp
This review is somewhat strange: it is made from the point of view of a swing dancer (the dance party is held weekly). The bar itself has a cool vibe, offers good martinis (about $18), the bartender is friendly. The stars, however, reflect the place as a dancing venue.
The dance party occurs every Tuesday form 6:30PM to 9:30PM and goes to live music (there is no cover). Format-wise, it is similar to the events in DecoDance bar on Wednesday - but on a better dance floor and with a band instead of DJ.
The venue: this is a relatively small bar with a relatively large (for the bar's size) dancing floor, good for about 10 couples. The place holds multiple dance events on weekdays (and weekends, but I would expect the vibe to be different). The floor is of excellent quality, and the spills - an inevitable issue while dancing in the bars - are cleaned immediately, so you should consider bringing your good dancing shoes. The dancers seat everywhere: at the bar itself, in the booths, on the benches ringing the dance floor. The bar is within an easy walking distance (a block) from a BART station, and the neighborhood is clean (by the SF standards).
The music: on my visit, SF syncopators were playing. The band was excellent, the sound level and acoustics just right. In other words, it was fantastic, a level completely unexpected from a no-cover event. When the band takes its breaks, some non-danceable music is playing .
In my experience, the bar events in general tend to attract a relatively tight-knit crowd. This particular group appeared to me somewhat younger - and much less tipsy - than the one at a typical swing dance party held at the bar. Skills I have observed were mostly between high-intermediate and amazing. While the dancers were quite welcoming, if you are like me (a past-my-prime intermediate lead), I would recommend (as for any other bar) either bringing your own follow or investing into socialization. You will definitely need a partner at 6:30PM: many regular appear an hour or more late. Figuring out the bar patrons who came to dance was easier than usual due to the benches around the dance floor and the group tending to stand together next to the bar.
Overall: if you are in SF on Tuesday and have your significant other in tow, highly recommended.